First an introduction (sorry, if this got a little long, just wanted to make clear for everybody what we are talking about).
What is a scheduler?
The scheduler is a built-in part of the Linux kernel. It is that part of the kernel which decides how the available cpu power is divided among all running processes. As the cpu can only work for one process at any given time, the scheduler is responsible to assign cpu time-slices fairly to running processes.
Because of this the scheduler (among other things) plays an essential role on how responsive a system "feels" for the user. That's because responsiveness depends among other things on the time how long it takes from user input until the cpu handles the input (i.e. until "your" task/process gets cpu-cycles).
Current state of the art:
The standard Linux kernel uses the so called "Completely Fair Scheduler" (CFS) since some time (October 2007) now and seems to be useful for most use-cases (server, desktop, smartphone..).
As you may have already heard, since August 2009 there is a new player on the field, namely the "Brain **** Scheduler" (BFS). BFS promises some better latency behaviour on smaller platforms with fewer cpu-cores and mobile devices. Altough it wasn't accepted into the official Linux kernel tree, it was used by cyanogen and also adopted by Google into the mainline Android kernel (and as we are having kernel sources now, I'm sure you will see some more BFS-enabled kernels for the Hero, too).
But back to topic:
So, what I am going to talk about applies to those of you who DON'T have a kernel with the BSF scheduler (i.e. which have the standard CFS scheduler) which should be the majority of ROMs at the moment.
Tuning the CFS scheduler:
Even it's said that BFS may be better for small devices it's also possible to configure CFS for our needs:
While searching around I learned that the behaviour of the CFS scheduler can be influenced at runtime by a few parameters. All these settings can be applied at runtime and will be gone after a reboot. So it is safe to play around a little bit.
One interesting parameter I found was "NO_NEW_FAIR_SLEEPERS". As stated by some people on the Linux kernel mailinglist :
NO_NEW_FAIR_SLEEPERS is something that will turn the scheduler into a more classic fair scheduler (like BFS is too)
Click to expand...
Click to collapse
If this is true, maybe it will let the CFS behave better optimized for small devices.
But let's try it out! Let's see if it gives us some improvements.
How to to this:
Code:
# Step 1: Mount debugfs (which is a virtual filesystem like /proc/ or /sys/)
mount -t debugfs none /sys/kernel/debug
# Step 2 (optional): Display the current scheduler flags
cat /sys/kernel/debug/sched_features
# Step 3: Set the flag NO_NEW_FAIR_SLEEPERS
echo "NO_NEW_FAIR_SLEEPERS" > /sys/kernel/debug/sched_features
# Step 4: Unmount debugfs again
umount /sys/kernel/debug
As said before: These changes are NOT PERMANENT. They will be gone after a reboot. But therefore it's safe to play around here.
Testing:
Tuning the scheduler will not give you plain speed improvements, so testing with Linpack is useless here. Instead it changes the way how the system reacts if there is a lot of multi-tasking.
So when you have changed the settings try testing around a little bit when the system is under load (like playing music while doing CPU intensive stuff or things like that) and report if it behaves better/worse than with default settings.
How to undo the setting:
Simple reboot your phone.
Or redo the steps above and replace the command in Step 3 with this one (note that the prefix "NO_" is ommited here):
Code:
echo "NEW_FAIR_SLEEPERS" > /sys/kernel/debug/sched_features
Feel free to test and share your findings!
I guess I can copy paste the lines and use GScript to run them.
Any way to make this permanent? Put something in init.d maybe?
Geochelone said:
I guess I can copy paste the lines and use GScript to run them.
Click to expand...
Click to collapse
Of course. You will find 2 scripts for gscript in the attached zip-file:
enable_CFS_tweak.sh
disable_CFS_tweak.sh
So you can simply switch for easy testing.
For those who don't know GScript: It's an app from the market to easily execute scripts on your phone. Pretty handy if you are testing things before you add them to an init-script.
Instructions:
Install "GScript Lite" from the market
Unzip the 2 scripts and place it on the sd-card into the folder gscript
Launch GScript Lite, press "Menu" -> "Add script" -> "Load file" and select the scripts you just placed into "gscript" folder.
Make sure the "Need SU?" checkbox is checked and press "Save"
Tap on the script to launch it.
Geochelone said:
Any way to make this permanent? Put something in init.d maybe?
Click to expand...
Click to collapse
Correct. You would need to place the commands into an init script, which are located in "/system/etc/init.d" on most ROMs.
Hard to test..
I underclocked my Hero to 245Mhz, started the music player, launched NeoCore benchmark and via adb launched 10 instances of "md5sum /dev/urandom".
Music still not choppy. No matter whether the tweak is enabled or disabled.
The scheduler seems too good to exploit it..
[edit]
just got a NeoCore benchmark if 02.8 FPS Yeahh, that's stresstesting..
[/edit]
is there a way to make this by default in the source?
maybe add the option to the .config file?
MaXo64 said:
is there a way to make this by default in the source?
maybe add the option to the .config file?
Click to expand...
Click to collapse
Yes, you can edit kernel/sched_features.h
and replace
Code:
SCHED_FEAT(NEW_FAIR_SLEEPERS, 1)
with
Code:
SCHED_FEAT(NEW_FAIR_SLEEPERS, 0)
thanks mate, compiling right away..
what is the test result?
Just so you guys know we are basically doing this now on the Eris... via some cool scripts:
http://forum.xda-developers.com/showthread.php?t=784089&page=7
Thanks for the tip will definitively check it out
Wow! Thanks for the tip. After reading it sparked my curiosity in the Linux kernel so I went hunting on the web for more detailed info on this particular parameter (NEW_FAIR_SLEEPERS) but I found no useful info as to what exactly it is or what it does. unfortunately, the name doesnt give too much away either (to the layman).
Anyway eventually I came across a site that a couple of other SLEEPER parameters are mentioned. and it claimed that tweaking these as well as changing the sched_latency and sched_granulairty parameters will enhance android phone performance. Again I searched for explanations of these parameters but to no avail (im obviously not very good at searching!). In the end I thought id just apply the tweaks and see what happened. and voila! the phone is the smoothest I have ever felt it!
As I said I dont know which tweak is responsible for the smoothness or if its just a combination of all three but my phone is really nice to use now. I can scroll long lists and actually see scrolling instead of a stutter from start to finish! I am running elelinux 1.8 and flykernel10a at 528MHz and its smoother than i've had it when running at > 600MHz.
I have no idea what implications the changes have on the overall performance of the phone but its smooth and not overclocked! cant be bad??
so heres the changes I applied: (from ./adb shell or terminal emulator on phone)
$ su
# mount -o remount,rw /system
# echo 'kernel.sched_latency_ns = 600000' >> /etc/sysctl.conf
# echo 'kernel.sched_min_granularity_ns = 400000' >> /etc/sysctl.conf
# echo 'kernel.sched_features = 24188' >> /etc/sysctl.conf
# mount -o remount,ro /system
# sysctl -p
kernel.sched_latency_ns = 600000
kernel.sched_min_granularity_ns = 400000
kernel.sched_features = 24188
# exit
$ exit
the 24188 parameter disables a couple of sleepers and the other two change some timings in the kernel. The changes are supposedly ONLY suitable for non-BFS kernels. but they are supposed to make the CFS kernel behave more like the BFS kernel in general.
Anyway try it and see if you want and report back if it makes your phone any better or worse. Or if there are any Linux gurus maybe you can shed more light on what these parameters actually do.
I know this thread is a little old, but I wanted to report that those settings worked great on my MyTouch Slide! I'm also overclocked/underclocked to 825/245 and using the autokiller memory optimizer, with the settings you suggest my phone is amazingly fast!
I did a little research on these settings as well, and will report back as I do some more testing to see what works best with the specs in this specific phone. At that time I will post a link to a new thread on this in the section for my specific phone.
Thanks for the great tips!
Hey guys,
Seems there's a lot of ways you can improve the speed of Android in general. Some seem to be snakeoil... others, work quite well and there's proof to back it up.
I'm only interested in discussing the latter .
A lot of people have helped me gather a better understanding of Android (hyc, stinebd to name a few) in addition to a lot of Google searching. I am going to compile a list of what I have done, I would like to hear what you guys have done! Most app killer apps / app control will already be addressed, so those tools need not apply... I'm looking for real, permanent fixes here without adding more apps!
I am also trying to have topics that are easy working up to advanced. Obviously the more advanced topics are going to be harder to do. You've been warned.
So here's the disclaimer.
****DISCLAIMER****
Speed is as always relative. That basically means I don't want arguments about which build is faster. I want to argue about how to make every build faster .
Also, these tips should apply to any build, any device... they are pretty generic tips, but are obviously specific to Android, with some idiosyncrasies that apply to our port that wouldn't apply to native Android devices. Some is common sense, others are real ways to tear into the system. Hope you enjoy it!
Topic 1
Difficulty Easy - Apps/Widgets
I've noticed the number of widgets i have on my screens, or the number of apps that I have installed/are running in the background to greatly effect performance, in an obviously negative way.
Once I removed all the widgets (I only have the basic analog clock widget & the Google search widget on one desktop...) this seemed to improve general speed. One minor thing to check is if apps are set to auto/background sync. Only enable the ones you really want syncing, others just check manually.
On this same topic, replacing the launcher (the stock launcher in Android, Launcher2 is quite slow) can help immensely. I like ADW, but I've used LauncherPro in the past and it is good. Zeam also seems like a good launcher. I haven't used Go Launcher EX, I've heard good and bad things about it. Use what works best for you, try 'em all!
The last thing on this topic I would like to mention is animations. Settings -> Display -> Animation -> No animations can make the phone feel quite a bit snappier, obviously at the expense of the look/feel of the OS.
Topic 2
Difficulty Easy - Controlling app 'net Access
This leads me into the next topic, DroidWall. I've noticed that blocking apps from accessing the internet has been a very good thing - it's not so much a performance booster (although it probably does provide a little bump) it's mostly about battery life. Just be warned, if you block an app that is set to background sync, it will probably have very negative effects. Only disable an app's access to the internet with DroidWall after you've checked that app's background sync feature is disabled. I have a few apps allowed in DroidWall, and the rest are blocked. You can "whitelist" everything and check apps you want to block, or "blacklist" everything and check the apps you want to allow. It's a little annoying to remember to enable/disable DroidWall (I use the DroidWall widget to enable/disable it globally) but if you do, it is much better - you have complete control over how apps access the 'net on your device. It is available on the Market.
Topic 3
Difficulty Moderate - SD cache/readahead tweaking
The only reason I'm calling this one 'moderate' is the number of choices you have for settings for this... It's basically telling the SD card how much to hold on to or... read "ahead" if you will . This was turned way up in FRX07, (from 256kb to 2048kb or 2mb...) and I think this might be the source of a lot of the complaints of 'mini-resets' if you will where the boot animation is suddenly seen after a long system hang...
So some cards will work better with a larger setting - I've heard some with spankin new C6 cards that said 3072kb or 3mb was a good setting. Others have found a sweet spot at 256kb or 1024kb (1mb).
There are two ways of doing this - you can hack the init in the rootfs and adjust the setting manually, or be lazy like me and use SD Booster (from the Market). Adjusts the same settings, and they are applied immediately!
I would like to find a "sweet spot" - a good default if you will. Can folks test out 512kb and 1024kb, see if you have any more mini-resets within Android or any other slowness, etc... Obviously this isn't a cure-all for the slowness or the mini-resets, what we're looking to do is mitigate the effects. So let's focus on that, thanks!
Topic 4
Difficulty Moderate - Overclocking
Overclocking is obviously one relatively easy way to improve the speed of Android. In your startup.txt, add a line
Code:
acpuclock.oc_freq_khz=710400
for example to overclock to 710.4mhz. How did I find this value? I actually put in 714000, but if you look at dmesg near the beginning you'll see "ACPU running at ..." - that's what clock is the actual maximum. It goes in 19.2khz increments.
Feel free to experiment with how high your phone can go, just be warned that the higher you go the potential for failure goes up as well . Phone shouldn't blow up, but it might not work correctly or at all. Rebooting and scaling it back will fix it.
Here's the full *example* startup.txt:
Code:
set ramsize 0x10000000
set ramaddr 0x10000000
set mtype 2292
set KERNEL zImage
set initrd initrd.gz
set cmdline "lcd.density=240 msmvkeyb_toggle=off gsensor_axis=2,1,3 pm.sleep_mode=1 physkeyboard=rhod400 acpuclock.oc_freq_khz=710400"
boot
You can put the command anywhere in the cmdline section, just make sure it's between the quotes and at least one space between each command.
Topic 5
Difficulty Advanced - How Android Manages Memory/apps
Ok, I'm going to take two approaches to this. The first, is the full explanation on how Android manages memory.
Please feel free to read the post I originally read that inspired me to start looking at this stuff - How to configure Android's *internal* taskkiller. It was very helpful for me to grasp how Android manages applications. This is the reason why application killers are not a good thing...
If you want to do it manually, Starfox suggests:
Code:
echo "1536,3072,8192,10240,12288,20480" > /sys/module/lowmemorykiller/parameters/minfree
To try to do these commands, adb is very useful. Once you get adb shell working, then you just need to "su" (provides 'super user' privileges (root)) and put in the echo command above ^^.
I had another user (thanks icevapor) suggest this script -
[Script] V6 SuperCharger! HTK & BulletProof Launchers! The ONLY Android MEMORY FIXER!
I tried it myself, and it works very well. This thread is a little overwhelming, but the jist of it is this:
Install Script Manager (on the Market)
Run the V6 SuperCharger script. I use "Aggressive 1 Settings" (#2) and then I use the OOM Grouping Fixes & "Hard to Kill" launcher (#17)
Point Script Manager to run /data/99SuperCharger.sh to run as root & on boot. This will ensure the tweaks are reapplied after a reboot.
Topic 6
Difficulty Advanced - Managing Apps that auto-start on boot
This is one of the most annoying things in Android. When you have no apps installed, it seems very fast. Then you install apps, and you never seem to get that original speed back... Now you can!
This is kind of difficult to do, I am still getting the hang of it... but here goes. All credit goes to hyc, his original post.
The basic idea here is you run a logcat (adb logcat is easiest here, or you can use GetLogs to pull logcat...) Look in this log for "for broadcast" and find apps that start on boot. For example,
Code:
Line 41: I/ActivityManager( 1394): Start proc nextapp.systempanel for broadcast nextapp.systempanel/.monitorservice.BootReceiver: pid=1752 uid=10060 gids={3003, 1015}
Notice there are two sides of the "for broadcast". The name of the package (nextapp.systempanel) and the name of the service, "nextapp.systempanel/.monitorservice.BootReceive". I made the mistake of disabling the app (the left side). Do not do this, you want to disable the right side!
So in the shell,
Code:
pm disable nextapp.systempanel/.monitorservice.BootReceive
This will be persistent across boots, it will go with your data.img.
Obviously this was just one example of an app to disable. So long as you disable the right side (after the 'for broadcast') you shouldn't disable anything that will cause a serious problem. The apps should still work, but for example if you disable Google Voice you won't get messages until you open the app. So think about that... You disable Titanium Backup schedules.BootReceiver, the schedules for Titanium Backup (if you have any) won't run. Stuff like that. Disable calendar, you won't get calendar events... Disable clock no alarms. Get it? Good. I have been rebooting several times, and I keep checking what is set to start on boot. I'm not quite happy with it yet, but there's some things I'm leery of disabling. Just be wary, if you do disable something and don't like it - just pm enable <whatever you disabled>.
Now experiment away! The one caveat is if you do break something with pm disable (and it's serious) you might get a failure to boot. It really depends on how bad you mess up. If you make a copy of your data.img before you start making these changes, you can revert to that data.img and start back there.
Alright guys. Going to use this thread as a way to brainstorm about ways to improve the speed. Read up what I've posted, let me know if I did anything wrong... Also let me know what you guys do to improve speed!
Don't care about what build you're running, this thread isn't about what build is fastest - this is a how do I make every build faster thread.
I also realize I posted this in the Rhodium section - I want to see if there's any BLAC-specific tweaks that others should be made aware of!
Thanks. Great posting. Will try some of the topics I never used (because I didn't know about them).
ThaiDai said:
Thanks. Great posting. Will try some of the topics I never used (because I didn't know about them).
Click to expand...
Click to collapse
I'm sure there are more as well... These are just the ones that I found made the most difference on my device.
I'm also curious about the minfree setting. I've only tried a few settings, they seem good. I haven't done any drastic number changing, it seems like changing these values should be done with a lot of caution and testing. There are definitely some values that should not be touched and others that can take some more fudging with numbers .
Added Topic 3 and Topic 4 to startup.txt and rootfs.img.
Just booting. Let's see if this is stable.
Software options I do not test now because I only test the new versions now. So specific app optimization only necessary when ThaiDai Android Loader and installation procedure reaches v2
Ok, boot ok, started Android (NeoFROYO build(, will tell tomorrow if stable.
If so I will use this options as standard for Blacky and I will add software like Droid firewall.
Thanks and good night
Update - I redid topic 4, feel free to re-read it.
Thanks
Enviado desde mi FROYO BLUE CWM1.9 usando Tapatalk
Hi Arrrghhh!
Can a squashfsed and odexed apk boost speed inside Android OS?
john_matrix said:
Hi Arrrghhh!
Can a squashfsed and odexed apk boost speed inside Android OS?
Click to expand...
Click to collapse
No clue. What does that have to do with the Speed Improvements thread?
I'm guessing you tried and it didn't work? What APK!?!
I guess I don't really follow your train of thought. Does sqshfs'ing and odexing an APK make it run faster...? I'm pretty new to Android in general. Never even used a native Android device .
http://www.addictivetips.com/mobile/what-is-odex-and-deodex-in-android-complete-guide/
http://forum.xda-developers.com/showthread.php?t=709630
farukb said:
http://www.addictivetips.com/mobile/what-is-odex-and-deodex-in-android-complete-guide/
http://forum.xda-developers.com/showthread.php?t=709630
Click to expand...
Click to collapse
I still don't get what that has to do with our builds. ODEX and DEODEX have nothing to do with our builds... That stuff only applies to native devices, or builds that are ported from native devices (I would think).
Perhaps I'm missing something here... please tell me if I am .
Maybe they mean something else like: oxidized or deoxidized (reduced) apps. With these modified apps you can speed up the transfer of electrons, resulting in more performance without overclocking your cpu. And more: it will not reduce your battery capacity measurable. I used it in some of the builds I tried. You will get a nice small benefit also: because of the electron transfers you will get a small induced massage in your fingers for free.
ThaiDai said:
Maybe they mean something else like: oxidized or deoxidized (reduced) apps. With these modified apps you can speed up the transfer of electrons, resulting in more performance without overclocking your cpu. And more: it will not reduce your battery capacity measurable. I used it in some of the builds I tried. You will get a nice small benefit also: because of the electron transfers you will get a small induced massage in your fingers for free.
Click to expand...
Click to collapse
LOL!
Epic.
OK. I cant get V6 SuperCharger script to work! I downloaded the script and run it but I cant find /data/99SuperCharger.sh after I run it
x12CHRIS18x said:
OK. I cant get V6 SuperCharger script to work! I downloaded the script and run it but I cant find /data/99SuperCharger.sh after I run it
Click to expand...
Click to collapse
Did you make the choices in the script, or did you just exit the script?
You have to make sure ScriptManager is running as root too. There's a setting for it. "Browse as root" - make sure that is enabled. You won't be able to see /data without browsing as root.
...You have a TouchHD? I always thought you had a RHOD, lol.
Attention!
If you're looking for scripts, here it is:
[CWM][SCRIPTS][TWEAKS] Thunderbolt!
Script Reviews are here:
Script Reviews
Introduction
I've been meaning to share this with the whole Android community. It seems unfair that only the i9000 folks have access to the vast research that I've done so far. Hence I'm sharing this in the general Android thread in hopes that it'll benefit everyone in the long run
A lot of people often asked about how Android really works and the optimizations can be made to their Android to make it perform better in terms of:
- battery life
- raw performance
- GUI smoothness
With Android based on Linux, and with the experience I have with Linux/Unix (I deal with Unix/Linux on a daily basis for my work) I managed to find some tweaks that we can do to optimize our phones.
I also hope that people will experiment with the tweaks posted here and feedback to me if there are certain ways that I'm doing incorrectly or there are better ways than what I've posted here.
Script tweaks
There are a lot of scripts in XDA that specifically uses the optimizations (Linux or Android based) that I will explain below to actually increase performance/battery life. However, you need to know what those scripts do before using it.
I've done some reviews of the script here:
Script Reviews by Pikachu01
There are good scripts that are properly tested and made sure that it works. It's a script by Zacharias maladroit, the kernel dev who makes the platypus kernel for CM7 and snail kernel for i9000. I modded it to be compatible with i9000 and it'll probably do more than some of the scripts I reviewed
From there, I've also taken the liberty of modifying it some more based on my knowledge and research I've done. It's called ThunderBolt!:
LINK
Now onwards to what actually goes on beneath the hood.
Android Governors
Some custom kernels provide customized governors for you to choose. These are currently known:
- Ondemand (CPU scales to the highest frequency immediately after a certain CPU threshold)
- Conservative (CPU scales to the highest or 1 scale lower than that after a certain threshold gradually and scales down if CPU is below a certain threshold
- OndemandX (Has sleep codes that scales down the CPU when device is asleep. Threshold is set to scale slower)
OndemandX
OndemandX has a suspend frequency that it maintains when the phone is sleeping. It does have a known issue of waking up too slowly when a call comes in.
Conservative
Conservative is used when you would like the CPU to scale to the maximum through each frequency slowly before reaching the maximum. It saves more battery at the expense of smoothness. There are a few tunables that can be configured in Conservative governor, namely the freq_step and both the up and down thresholds.
freq_step is a tunable that determines how much frequency (a percentage of the maximum frequency of your device) to increase at each sampling rate. e.g. you have 5 as freq_step and your maximum frequency is 1GHz. At each sampling rate, it'll increase by 50MHz. If your current frequency is 100MHz, it'll increase to 150MHz at the next sampling. What if your device doesn't support 150MHz? This is done by splitting time between 100MHz and 200MHz (assuming your next frequency is 200MHz) so that in average, your phone is performing at 150MHz.
The up_threshold is how much threshold to wait for before increasing the base frequency to the next freq_step. I.e. if it is 80, the CPU will wait until it is 80% loaded before increasing the frequency. The down threshold is the opposite of up_threshold, which is the threshold to wait until the CPU downscales the frequency to the next frequency step.
Ondemand
Ondemand is a governor that basically a simpler version of conservative. One difference is that it scales to the maximum frequency after load has exceeded a threshold. This is usually 80. After that, it looks at the load again when it's at the max frequency. If it's below 80 (example), it'll scale down one frequency step. The frequency step mentioned here is the available frequency step. I.e. if your device has frequencies of 100,200,400,800 to 1GHz then it'll scale down from 1GHZ to 800, 400 then 200 and 100.
One optimization I have for Ondemand for i9000 TalonDev is that I tuned it to be 80 rather than 65. I have not felt any slowdowns from using this setting and it saves a tiny bit more battery. You can experiment on this value however you want, but bear in mind that I'm not responsible for any slowdowns or damage that is caused by it. Read up a bit more on thresholds to know more (Google it).
I/O scheduler tweaks
Another tweak that can be done is the I/O scheduler tweak. Some kernels come with a few standard I/O schedulers while others have extra schedulers that you can choose from. I'll explain the few that I know and if you have more information on the schedulers, you can post it here for everyone to discuss/share
CFQ - Completely fair. Most will come with this, but this is not optimized for android. Some kernels do optimize it and use it.
Noop - Simple and least overhead of all I/O schedulers. Produces the best outcome for some cases and some do swear by it. It's downside is that it is easily bogged down by high I/O transactions.
Deadline - Optimized for mobile-like devices like Android. Also, some do swear by this. If its writes_starve sysfs is tweaked to be fair, it's the same as SIO.
SIO - It's a fair deadline scheduler. It's the best scheduler. Nuff said.
VR - A newer I/O scheduler that places penalty on reverse seeks. Not for flash drives, though the R penalty can be tweaked to be a multiplier of 1. Even if this is done, it has a high overhead.. Read more here: http://www.gelato.unsw.edu.au/IA64wiki/IOScheduling/VRscheduler
BFQ - Too high of an overhead, it is optimized for spindle disks.
You can pick and choose from Voltage Control or other UV/OC apps and apply it immediately to feel the difference.
Here's my assessment of all the schedulers that I know:
SIO> NOOP> Deadline > VR > BFQ > CFQ
NOOP is a simple I/O scheduler without overhead that tries to do each I/O transaction as it comes (FIFO). When a group of transactions is detected, it will try to merge it together to make batches of transactions (makes the whole transaction faster). NOOP doesn't have starvation detection, hence if an I/O transaction takes a painfully long amount of time, it will still continue to do it rather than switch the CPU into doing something else e.g. GUI interrupts (i.e. scrolling lists, flicking screens). All other schedulers also have the "merge" feature. NOOP is the only one that makes the "merge" feature its only feature.
CFQ is a complex I/O scheduler that tries to determine the address space of the transaction and applies a cost algorithm in that if the address is close together, it will group them up and perform them. It also tries to make the transaction incremental (i.e. reading/writing through address incrementally so that the disk spindle needs to wind down the least in conventional platter hard disks) The problem is, our flash devices have very little delta between reading a far reaching address space (than the one currently being written/read) or a closer one as it doesn't rely on spindle/rotations. Hence, having this costing algorithm adds overhead and slows down the overall transaction. CFQ has a lot of algorithms to make sure each process gets a fair slice of time on I/O transcations. Too much overhead.
Deadline has a starvation detector and is simple enough that it doesn't have all the overhead of doing rotational/costing disks algorithm. However, reads are done 2x more likely than writes as it has a algorithm based on weights in that reads must be done first if both a read and a write is detected. It has a 2:1 ratio of read to write weights coded into the scheduler (that can be tweaked - writes_starved, will include it in the next version of system_tweak). Hence it's not a fair scheduler.
SIO is Simple I/O that tries to implement a NOOP type scheduler that has starvation detection. Hence, long I/O transactions will be preempted and given CPU time only after other faster transactions are completed, guaranteeing smoothness. Also, it doesn't have overhead of calculating costs. Also, it has a fair number of writes to read, guaranteeing that all transactions are equal.
BFQ has a lot of algorithms to make sure each process gets a fair slice of bandwidth (Budget Fair Queueing). Too much overhead.
V(R) tries to make sure that each transaction has a weight associated with it, being R. And if the seek is reversed, the R will be multiplied by a penalty making it less likely to be processed. Not for flash drives as reverse seek in a flash drive is just as fast as a forward seek.
In benchmarking tests, the tests normally consists of testing the time it takes for a contiguous I/O transfer from 1 point to another. NOOP excels at that because it won't let itself get interrupted to perform another I/O task. This would mean that in real life testing, NOOP will let a long arduous task to finish while at the expense of UI functionality (you will get UI lags)
SIO on the other hand will perform badly at benchmarking as it gets pre-empted when the contiguous tasks takes more than 0.5secs (for synchronous tasks as benchmarking tools perform a synchronous I/O task from one point to another) to another more important task like UI interrupt (when you're scrolling) or Kernel interrupt (when your kernel needs to perform garbage collecting or swap memory etc)
The 0.5 secs can be tuned in the SIO tuneables though, but I would think 0.5 secs for synchronous tasks and 5 secs for async tasks is pretty good to maintain a balance between long/short tasks enabling a smoother experience in Android.
LowMemoryKiller
The LowMemoryKiller is a constant debate between more free RAM and more multitasking capabilities as free RAM (more than 60MB free) is actually wasted RAM. The fact is SGS only has a puny amount of RAM left after a few big chunks are allocated to the Graphics, Modem, Sound and Video (and some others that I do not know a lot about). With that knowledge, Samsung decided to give the SGS SL a bigger amount of RAM when they released it ( about ~650MB of RAM read that from somewhere, can't remember).
The LowMemoryKiller is actually a feature in the Android OS for better memory management.
You can read about it more here:
http://forum.xda-developers.com/showpost.php?p=5442369&postcount=1
This is an important feature due to the perennial problem of having low free memory causing lagginess and slowness in launching apps. When you have free memory lingering around the number of 40MB or less, the Android OS just lags like hell.
What this would mean is, you would want to tweak the LMK to not have the situation of it having less than 40MB (or even close to that).
The modern Linux machine in the Android ecosystem relies on a mechanism called Low Memory Killer (LMK) to consistently free up RAM. This is due to Android's internal mechanism of caching apps (and never fully exiting them) when you press the back button. This is to enable faster app switching and provide a seamless experience for apps usage model. Android also, by itself will also constantly look for often used apps to cache them for faster app opening. This will happen even before your system fully boots.
Now, when you mention LMK, the most obvious thoughts that come up are minfrees and Out Of Memory (OOM) groupings. Yes, those two are integral parts when it comes to LMK. The issue here is that no one actually mentioned that there are two LMK systems in Android, that being:
- Linux LMK
- Android Dalvik VM LMK
Both are separate entities that kills/removes app/dalvik cache from RAM when RAM reaches a certain level.
What confuses most people (including me) is that the OOM groupings of both mechanisms have the same names being (Android 2.3 based):
LMK App Categories
FOREGROUND_APP: Your apps in the foreground, being used currently, interfacing with the user.
VISIBLE_APP: Visible app that is still viewable by the user, but not interacting with the user, example could be apps that reside in the status bar, and giving live information i.e. Os monitor graphs.
PERCEPTIBLE_APP: App that the user can still perceive i.e. Music app that is playing music.
HEAVY_WEIGHT_APP: RAM heavy apps that are not being interacted with, but will be a pain to load if its information is cleared in the memory.
SECONDARY_SERVER: App that acts as a secondary server. Not sure what this really means, but client-server thingy but secondary? Could be something that syncs with an app, but is not syncing currently?
BACKUP_APP: App that is currently making a backup (like Titanium backup?)
HOME_APP: Your launcher.
HIDDEN_APP: An exited app that still significant residual memory in the RAM. Exited only some time ago, or is constantly used by the user.
EMPTY_APP: An exited app that only has small remnants of residual memory in RAM. App that is exited quite some time ago.
Take note that this is my understanding of the OOM groupings. If there are mistakes, please correct me
Tuning LMK
Both the LMK and Dalvik VM has this groupings and they can be tunable by using prop and lowmemorykiller/parameters/adj respectively.
One errata about this is that the Dalvik LMK has one extra tunable which is CONTENT_PROVIDER, which affects widgets that are not currently refreshing or displaying information. The ADJ (which I will explain later) is not available to be tuned though. And it is clearly missing from the Linux LMK.
The ADJ is the so-called priority of the app categories, with 0 being the highest (should not be killed) and 15 being the lowest (should be the first to be killed). I haven't seen values other than 0-15 but I have a feeling that the numbers are arbitrary, and can be extended up to 65535, but who would want to do that since they're only 9 app categories
LMK are specified by pages, with memory = 4 * pages.
e.g.
4096 pages represents 16MB RAM (16 *1.024)
From the Linux LMK source code, the parameters can be adjusted as such:
Code:
* For example, write "0,8" to /sys/module/lowmemorykiller/parameters/adj and
* "1024,4096" to /sys/module/lowmemorykiller/parameters/minfree to kill processes
* with a oom_adj value of 8 or higher when the free memory drops below 4096 pages
* and kill processes with a oom_adj value of 0 or higher when the free memory
* drops below 1024 pages.
Take note that the oom_adj so far takes only 6 values (although I am confident that it can take more than that). Haven't experimented enough to validate that, but I shouldn't need to as assigning different oom_adj should be a given for all the app categories. This is to make the LMK intelligent enough to determine which app to kill first rather than grouping different app categories into one priority, in which a lot of popular LMK settings that devs provide do that.
And for the Dalvik LMK, my understanding is that it will remove all dalvik caches of <INSERT_APP_CATEGORY_ADJ> or higher if free RAM/pages reaches the level specified.
Hence, two things are learned here:
- Linux LMK will kill an app category of that particular RAM level or higher if free RAM drops below a certain level e.g.
Hidden_APP has a minfree of 16384 pages. If pages fall below this level, Empty_App will be killed first, free pages is recalculated, then if RAM is still below that, Hidden_Apps will be killed next.
- Dalvik LMK will clear all dalvik caches in RAM of all the App category if free RAM reaches the level e.g.
SECONDARY_SERVER_MEM is 8192 pages. When RAM reaches 8192 pages, all SECONDARY_SERVER caches are cleared.
Best Practices
Now, how do we tweak both so that it is efficient in doing its job, i.e. LMK.
From my experiments I can safely say that:
- Below 60MB free RAM you will feel lag 5-10% of the time.
- Below 52MB free RAM you will feel lag 5-15% of the time.
- Below 46MB free RAM you will feel lag 15-20% of the time.
- Below 42MB free RAM you will feel lag 20-50% of the time.
- Below 36MB free RAM you will feel lag 100% of the time.
The experience of lag increases exponentially from 60 down to 36MB. Hence, the LMK should be tweaked against that.
Also, it is considered best practices to group oom_adj settings of Linux LMK with the Dalvik LMK as when free RAM drops to that level, both the Linux LMK and Dalvik LMK will work together to free up at both sides.
The 6 oom_adj that can be tuned for Linux minfree also need to be tuned correctly, failing this would make the LMK too aggressive/under aggressive in mid levels (even if your EMPTY_APP is aggressive, if your oom_adj is selected incorrectly, you'll get to a point where memory leak occurs).
Talon LMK - This is obsolete, TalonDev is using ThunderBolt! LMK from 0.5.x
Take for example, the Talon default LMK setting where:
LMK_ADJ is 0,1,2,3,7,15.
It's EMPTY_APP is 15
It's HIDDEN_APP is 5
It's HEAVYWEIGHT, SECONDARY and BACKUP is 3
Last three values of MINFREE is 4096, 9216, 12288.
Where's the issue here? If you noticed it congrats.
If you didn't, here's the issue:
The minfree 12288 is tied to EMPTY_APP which has a OOM_ADJ of 15.
The minfree 9216 is tied to nothing but has a OOM_ADJ of 7
The minfree 4096 is tied to HEAVYWEIGHT,SECONDARY and BACKUP with the OOM_ADJ of 3.
The LMK_ADJ is important as it represents the checkpoints where the Linux kernel will check for minfrees and kill them. Here's a situation:
Memory is below 12288 pages, OOM is triggered and Linux looks for EMPTY_APP to kill and kills all of them. Job done. Memory is back to >12288 pages.
After a few days, memory is below 12288 pages again, OOM kills all EMPTY_APP, but free memory is still lower than that. It sees if the next checkpoint is fulfilled, which is 9216 pages, and yes memory is still below 9216 pages. It looks for an OOM_ADJ of 7 and above to kill, but fails to find any as 7 and above OOM_ADJ only consists of EMPTY_APP.
Here comes the quandary. The next checkpoint is 4096. We're not ever going to reach that as you'll need memory to fall below 16MB, and at that time it'll be super sluggish to even support GUI. Hence BAM, memory leak or lag or something.
Supercharger LMK 512HP - Multitasking
Let me just paste this to avoid a lot of retyping
Code:
FOREGROUND_APP_ADJ=0
VISIBLE_APP_ADJ=4
PERCEPTIBLE_APP_ADJ=2
HEAVY_WEIGHT_APP_ADJ=5
SECONDARY_SERVER_ADJ=6
BACKUP_APP_ADJ=7
HOME_APP_ADJ=1
HIDDEN_APP_MIN_ADJ=8
EMPTY_APP_ADJ=15
FOREGROUND_APP_MEM=1536
VISIBLE_APP_MEM=3072
PERCEPTIBLE_APP_MEM=1024
HEAVY_WEIGHT_APP_MEM=10240
SECONDARY_SERVER_MEM=10240
BACKUP_APP_MEM=15360
HOME_APP_MEM=1024
HIDDEN_APP_MEM=15360
EMPTY_APP_MEM=25600
LMK_ADJ="0,4,6,8,14,15"
LMK_MINFREE="1536,3072,10240,15360,20480,25600"
A few things here:
It's EMPTY_APP and HIDDEN_APP is too large, 80 and 100MB respectively, but the 80MB is a false flag hence it doesn't really matter if you tweak that and you can get a very minor degree of multitasking because of this false flag. I'll get to that in a moment.
It's PERCEPTIBLE_APP has higher OOM_ADJ than VISIBLE_APP (odd selection, but RAM rarely goes below 40MB before it starts lagging like hell) People would reboot their phones when it gets to that, but it rarely gets to that for this configuration as LMK is pretty aggressive here.
Now, it's LMK_ADJ is "0,4,6,8,14,15"
15 is EMPTY_APP,
14 is nothing
8 is HIDDEN_APP - it looks like it'll only kill HIDDEN_APPs when it reaches 60MB, with HIDDEN_APPs being the heavy hitter of apps as most apps will end up in this category. Hence why multitasking is still doable (to an extent) but an aggressive LMK means taking a call or switching to a browser will kill your game (losing saves). Inconvenient, but it works for some people who haven't played a long game without saving and never took a call in between. Imagine the horror LOL!
Juwe's RAM Script
Code:
if [ -e /sys/module/lowmemorykiller/parameters/adj ]; then
echo "0,1,2,4,6,15" > /sys/module/lowmemorykiller/parameters/adj
fi
if [ -e /sys/module/lowmemorykiller/parameters/minfree ]; then
echo "2560,4096,5632,10240,11776,14848" > /sys/module/lowmemorykiller/parameters/minfree
fi
No OOM_ADJ are given, hence the stock ones are in effect here.
From init.rc, this is the stock 2.3.5 OOM_ADJ.
FOREGROUND 0
VISIBLE, PERCEPTIBLE 1
HEAVY_WEIGHT, SECONDARY_SERVER, BACKUP 2
HOME 4
HIDDEN_APP 7
EMPTY_APP 15
This one also suffers from the false flag of the 2nd last minfree not being used. It will start killing HIDDEN_APP at 40MB, which is usable (you'll only get lags 15-20% of the time, and most probably after long usage). Other than that, it's pretty stable.
Misc
There are a few known scripts that tweaks the LMK as well as the app priority (yes, the priority of the process categories can be changed too by using setprop.)
Supercharger is one of them:
http://forum.xda-developers.com/showthread.php?t=991276
Take note that Talon doesn't permit Supercharger to be used (it will override it when booting through boot scripts) as Talon itself uses its own LMK settings that are optimized for ZRAM/Swap.
Kickasskernel script is also included in Supercharger. The script will clash with Zach's script in ThunderBolt! too as both of them tries to set different values for the same settings.
Note that Zach's script doesn't tweak LMK settings as i9000 Talon doesn't permit it. With that, if you're using Zach's scripts, you would need to find other ways of tweaking the LMK. Using Auto Memory Manager is good. You can download Supercharger, look at the presets and apply it using Auto Memory Manager. The preset is the only thing important here
LMK App Category Priorities
Using setprop, there is a way to set the priorities of the category. Since, app categories are different, I can only offer one recommendation: The HOME_APP_ADJ.
This prop setting sets how high of a priority your launcher is. A 1 or 2 is sufficient to make sure your launcher doesn't get killed. However, do you really want it to be on 1 or 2. Based on the previous article (LMK/OOM), you would know that OOM priorities are comparatively based on one another. Setting it 1 or 2 in stock 2.3.5 values would basically override PERCEPTIBLE/VISIBLE app priorities. Do you want your launcher to be killed only after your keyboard/music player to be killed? You decide
Journaling/Barriers
This has been a touchy subject here in XDA for most people who debate about it. Most recently, the SAS/Acid tweaks included a way to disable journaling on these partitions:
/system (System is read only, it's safe to remove journaling. However, you will not see speed increase by removing it as you're not writing onto /system 99.99% of the time unless you're using Titanium backup to remove system apps or copying init.d scripts to it)
/cache (Cache can be rebuilt on the fly. Data corruption on it is not game breaking)
/data (All of your data on your phone is here. Removing journaling can risk data corruption. Read more below)
On whether we need journaling or not, I will pose this situation:
Journaling is required to maintain data consistency in events that could lead to data corruption. Data could get corrupted in a number of situations:
- Misbehaving app that constantly writes without syncing/committing data to the disk
- Power loss due to forced reboots or bootloops when data is partially written/committed into disk
Android will normally buffer its writes before committing to the disk. This way, data stays in the RAM before data would only get written into the disk after a period of time. Take note that we as Android enthusiasts seek ways to better our phone to get the most out of it through experimental and sometimes wacky ways. Take OC/UV for example. When we OCed or UVed too much, sometimes our phone will get deadsleep or constant reboots. This leads to corruption if journaling is not turned on. However, we can get corruption too even with journaling but the risk is smaller.
Mount options too, play a role in whether journaling can be safe/unsafe. Most lagfixes will place a "barrier=1" in the /data to make sure that journals are actually committed before an out-of-order write is done. With that, the risk is greatly reduced at the cost of performance. You could experiment by removing barriers and see if it works for you. No guarantees on data if you remove barriers! More info on ext4/barriers:
http://lwn.net/Articles/283161/
http://kernelnewbies.org/Ext4#head-25c0a1275a571f7332fa196d4437c38e79f39f63
If you do disable journaling, make sure to manually run an fsck on your disk. Make sure the fsck binaries are in your binary paths (echo $PATH to show your binary paths). Don't ask how to do this if you're unable to do fsck. It is your own risk that you are disabling journaling/barriers.
One experiencing I would like to relate is this:
I've personally disabled ext4 journaling on my device. After experiencing a sudden power loss (forced reboot), my apps started FCing left and right and device became unstable that it sometimes rebooted when the device is sleeping. In other words, it's a lost case. Reflashing was the only way to restore my phone. This happened 1 day after disabling my journals.
Also note that ext2 is basically an ext4 without journaling. However, ext4 is updated all the time while ext2 source is not updated for quite some time (2 or 3 years?). Most optimizations are already in ext4 while ext2 even without journaling is slower than ext4 without journaling. A comparison of performance:
No journal:
ext4 > ext2
With Journal:
ext2 (can't do journaling in ext2) > ext4 > ext3
Update: Attached is a JournalingOn.zip for i9000 only that you can flash to rejournal your partitions (Only for i9000 devices!). Also attached is Acid Tweaksv6 - Removed Useless Stuff that will disable journaling only for /system and /cache, if anyone is interested. You will need to rejournal first before unjournaling. To be sure that /system and /cache has no journaling and your mounts are applied correctly, type "mount" without the quotes.
You'll be able to see that /data will have:
Code:
barrier=1, data=ordered
/system and /cache will have:
Code:
barrier=0, data=writeback
To be really sure, you can check by using tune2fs included in both the JournalingOn.zip and Acid Tweaksv6 - Removed Useless Stuff.zip.
Copy the tune2fs to /tmp and set rwxr-xr-x as its permissions using Root Explorer/File Expert
Code:
/tmp/tune2fs -l /dev/block/mmcblk0p2 | grep features
You can substitute the /dev/block/mmcblk0p2 (which is /data) to /dev/block/stl10 (/dbdata) /dev/block/stl9 (/system) /dev/block/stl11 (/cache) to check each partition.
Continued in Post #2 - Lack of space
Still posting ...
Question
I guess this is safe too on a deodexed ROM, too freeze those bloatwares u listed?
Page 2
Undervolting/Overclocking
This is also another touchy subject, but more towards people complaining about phones that get forced reboots or bootloops. OCing is done to get better performance on your android. WARNING: Ocing will cause more wear and tear on your CPU and will reduce your CPU lifetime. How much it will reduce it? No one knows. It depends on how sturdy your CPU is, and that cannot be measured by any means. It could be reducing months out of year e.g. 6months out of 3 years? No one actually knows.
UVing on the other hand reduces battery drain especially when you UV your 100MHz as 90% of the time in normal usage, your CPU will idle at 100MHz. How much can it save? No one actually did a benchmark on it. Save to say, UVing does not harm your CPU, it will actually extend the life of it by reducing wear and tear Oh, bootloops do corrupt data if you're without journaling
Always remember to clear your UV/OC settings before flashing another kernel!
Take note that the ability to OC/UV depend on your phone. Some SGS can UV better or OC better and some might not.
On how to UV:
1. You can UV more on the lower frequencies than the higher frequencies.
2. Do a UV for
100MHz with (950-150=800) - Take note that 950 is the base value for the voltage. Some kernels might have changed this value to 925 or 900. This is why clearing your OC/UV settings is important as the OC/UV settings will only load the voltage difference, which in this case -150. If the base voltage is 900 and you do a -150 for it, you'll end up with 750 which might cause bootloops.
3. Limit the max frequency to 100MHz. WARNING: Doing this will significantly slow down your system to a crawl, but it is still running. This is done only to test the stability of your system. You can skip this if you want, but you would need to find a way to stress test your CPU at the 100MHz value (and other values as well by limiting the max frequency). Failing in testing this will result in deadsleeping (as your phone is in 100MHz when you sleep and if you undervolt too much, you deadsleep)
3. Test with RockPlayer (or MX Video Player) and play an RMVB file using software decoding for 10mins. If your settings is unstable, Android will freeze up and reboot. (this is just an example, but I find that this way stresses the CPU to the max. I fail to find another way of stressing it as even playing NFS is stable on some voltages but fails when I play rockplayer. Hence rockplayer is the best way so far)
4. After doing this, remove the limit and move on with the next few frequencies.
The rest of the voltages, just rinse and repeat.
200MHz with (950-100 = 850)
400MHz with (1050-75 = 975)
800MHz with (1200-25= 1175)
1000MHz with (no change)
You can experiment with lesser values than these if you get freezes/bootloops as this is by no means a one size fits all value. Some might think this UV is overly aggressive or some might think that this UV value is too underwhelming.
Mine if you're interested:
Code:
100MHz = -200 (950 base)
200MHz = -150 (950 base)
400MHz = -125 (1050 base)
800MHz = -75 (1200 base)
1000MHz = -50 (1275 base)
As for OCing, you would do the same to test the stability. Just that you will be enabling a higher clock for your L0 frequency (L0 is the highest frequency). Some kernels might add more frequency states i.e. from the 5 states above to 6. You can try using Tegrak OC app too. It all depends on your own experimentation.
Memory Leaks
If you found out that your Android is laggy after sometime and a reboot will make it faster, then you're experiencing memory leaks. "free" is a command to show your currently free memory. It will not necessarily be the same value as your phone's free memory (as it takes into account swaps and buffers)
1. Go to terminal emulator (or download the script at Post #3)
Code:
su <ENTER>
free <ENTER>
This will show your buffers and free memory.
My example:
Code:
total used free shared buffers
Mem: 348548 340280 8268 0 1320
Swap: 163836 47292 116544
Total: 512384 387572 124812
Then do this:
Code:
sync <ENTER>
echo 3 > /proc/sys/vm/drop_caches <ENTER>
Type:
Code:
free<ENTER>
And you'll realize that the buffers will reduce and free memory will increase, like this example:
Code:
total used free shared buffers
Mem: 348548 305212 43336 0 88
Swap: 163836 46804 117032
Total: 512384 352016 160368
That means it's done.
Click to expand...
Click to collapse
If this solves the laggginess problem, it's due to vfs_cache_pressure being too low and dirty_ratio being too high. However, in most cases, you don't have to do this as Linux will manage to clear the RAM in a timely manner as long as there are no apps that constantly hold on to the memory (not releasing it). Hence, only do this when necessary (lagginess and such).
With that, I've updated the system_tweak yet again, with this knowledge by making the VM settings more aggressive, which will trigger the memory leak faster. I made this so, as there's a workaround to clear the caches when it gets full.
Having a low vfs_cache_pressure and a high dirty_ratio will save battery and make your device perform faster at the cost of higher RAM usage.
You can actually automate it by using Script Manager by making a script, pasting the instructions and making a widget out of it. To learn more, read the android market description or the in-help guide in the app.
Some commonly asked questions about drop_caches that were answered by me from flolep:
http://forum.xda-developers.com/showpost.php?p=17727859&postcount=3428
http://forum.xda-developers.com/showpost.php?p=17731938&postcount=3446
http://forum.xda-developers.com/showpost.php?p=17736421&postcount=3450
Checking for Battery Drain/ Saving battery
Starting from Gingerbread, you can't really look for Partial wakelocks anymore to determine what is draining your battery at night. BetterBatteryStats is a way to check for that. It also can provide the process that drains your battery most of the time.
A high partial wakelock usually says that something is waking up your phone at night. With that, checking partial wakelock, you can see if these are the culprit:
-Network Location
-Location Manager Service
If so, disable Lattitude or any location check-in app that you're using. It's checking you in every few minutes that drains the battery.
Disabling Wifi/3G/HSDPA saves battery too. I find that Wifi/Edge drains the least amount of battery when idling. To switch to EDGE as opposed to HSDPA/3G.
Go to:
Code:
Settings > Wireless > Mobile Networks > Network Mode > GSM Only
Disabling "Use Wireless Networks" in location and security would save a little bit of battery too I guess. It's in:
Code:
Settings > Locations and Security > Use wireless networks
CSC
CSC is a folder that defines your APN settings and country/region specific configurations aside from Language/Time that is configured in build.prop(also for Samsung Apps).
Having to manually set your APN is annoying right?
Your product code being KOR by default is another annoying thing to deal with. How do I resolve this?
1. Get your CSC from your own country here: http://forum.xda-developers.com/showthread.php?t=948790
2. Extract from the zip file /system/csc/<folder> (where <folder> is your Country's CSC)
3. Use Root Explorer/File Expert to copy it to the phone's /system/csc/.
4. Use nitrality to change your product code. WARNING: This will wipe all your data.
Odexed vs Deodexed
I've been using Deodexed ROMs since I first flash my custom ROMs. One gripe I have is that I seem to have lost the stock smoothness/speed that I experience when I'm using a stock ROM. I found out that deodexing actually extracts the customization files back to the APK (using APK manager) and Odexed files are actually done to optimize the speed of those files itself.
The only reason ROM chefs are using deodexed files is that it is easier to theme. There is no need to decompile the odex files and make the changes as all the theme files are in the APK themselves.
Only other reason that I know of is the overscroll glow. Odexed files can't support it. However, that is a small price to pay for speed/smoothness that I am willing to sacrifice.
Busybox
Busybox is required to perform all of your superuser activities in your android phone. There are some problems associated with this when ROM developers decide to use a certain version of Busybox that are incompatible with the binaries that we use in our phones. When you found out that after changing your kernel/ROM:
- You still have superuser and Titanium Backup still works but,
- Root Explorer/File Expert can't copy files correctly to the /system after mounting rw
- Voltage Control/ Pimp My CPU/ Control Freak/ SetCPU cannot create the Svolt_scheduler file in /etc/init.d
You have a clashing busybox version issue. This can be remedied by:
- Installing the busybox installer from the market
- Installing busybox 1.17.x into /xbin
- Removing all other busybox binaries from your binary path. (This is optional if you found out that after installing busybox, everything works. Try it first before removing) To know your binary path, do an
Code:
echo $PATH
Nandroid Backup
Nandroid Backup is done in recovery (VolumeUp + Home + Power). In recovery, choose Backup And Restore. What it does is it backs up your:
- Boot
- System
- Data
- Cache
When you restore, you should preferably use Advanced restore and restore the /system and /data. All others can be built from scratch (except /boot). If you're converting from CM7 to Samsung Roms, it's best to start from scratch either ways. Restoring nandroid from any is considered dangerous and not supported by most cases. Best is to use Titanium Backup to backup as it can be restored both ways (only restore app though, restore data sometimes can lead to FCs)
Voodoo Color
Voodoo Color is also a point of contention among users. Some like it and some hate it with a passion. If your kernel does support it, here's a way to tweak it:
1. Tweak the color profiles. Can't see a difference, hence I would just pick Voodoo most of the time.
2. Tweak the gamma first to a comfortable value. I.e. drag the 3 sliders together to a comfortable gamma level. After that, try looking in the gradient (the gray slab below the slider) and try to find for neutral gray values. Adjust each slider until you find a neutral gray (i.e. left and right until you see that slab is truly gray)
3. Tweak the RGB multiplier until you have a comfortable level (3 sliders together). Then tweak it the same by referring to the gradient until you're comfortable.
4. Switch off your display for a while and look at your surroundings to reset your eyes. Then turn on your screen again and see if its too green/yellow/blue etc. Adjust the gamma/RGB multiplier until you're satisfied.
This might take a few rounds of testing, but in the end you'll be truly satisfied with it
i9000 Specific
i9000 Kernels - In Depth
You will need to have a stock odexed (why odexed? read a few passages below)ROM with root. You can easily do this by flashing stock XXJVS 2.3.5 and then flashing a custom kernel through Odin like:
- Dark Core - Uses Voodoo initramfs
- CF-root - Uses CF-root initramfs
- Semaphore - Uses CF-root initramfs
- Midnight - Uses Speedmod initramfs
- Galaxian - Uses CF-root initramfs
- Voodoo - Uses Voodoo initramfs
You can flash the custom kernel through Odin by placing the tar file into the PDA section and pressing Start. At this point, do not convert your partitions to ext4 (lagfix) unless you're using a Voodoo based initramfs as Voodoo based initramfs will convert your partitions to ext4 automatically at first boot.
After flashing a custom kernel through Odin, you will gain root. From there, you can choose to use any other custom kernels that use CWM to install or stick with the custom kernel that you've flashed through Odin like:
- TalonDev - Uses Voodoo initramfs
- TalonSH - Uses Voodoo initramfs
There are other kernels as well, but since I did not stress test them, I will not include them here. This thread lists the full repertoire of custom kernels that you can choose from:
http://forum.xda-developers.com/showthread.php?t=1196704
On which custom kernel to pick, you're advised to look at the individual threads original post as well as the last 5 pages of the thread to know about its stability and features. I pick TalonDev myself as it has compache as well as the latest upstream (kernel updates from the Linux OS as well as the official Android Open Source Project/AOSP and optimizations) patches.
At this point, you should decide if you would want to convert to ext4 (lagfix) or not. Your phone by default will reside in an RFS system. The RFS at this point in time is pretty stable and its performance can easily match ext4. Too bad Quadrant scores are bad for RFS, but who cares about Quadrant anyways. I myself choose to use ext4 as the TalonDev kernel has a lot of ext4 upstream patches that optimizes the usage of ext4 on Android.
If you're using Voodoo initramfs, you'll be converted to ext4 automatically.
If you're using CF-root initramfs, you will require the CF-root ext4 app to convert that can be found here:
http://forum.xda-developers.com/showpost.php?p=12651371&postcount=7
Note that on some kernels that use CF-root initramfs, the ext4 app will warn you that you're not on CF-root type kernels. Ignore this warning. You'll be able to convert to ext4 anyways unless you're on Galaxian. Certain Galaxian versions (since the kernels are not versioned, I can't tell which versions are not working) will bar you from converting to ext4 using the ext4 app. If that is the case, just flash CF-root, convert to ext4 and then flash back to Galaxian.
Also not that CF-root based initramfs kernels will remove your bootsounds on first boot. Don't be alarmed by this.
In terms of which lagfix is better (Voodoo vs CF-root lagfix), I can't tell at this point in time. Both are equally good. Since TalonDev uses the Voodoo initramfs, I am inclined to use the same when I am using the same kernel. That should be a good yardstick to follow.
BIGMEM/ Non-BIGMEM:
Some kernel developers released BIGMEM versions of their kernel:
-TalonDev BIGMEM
-TalonSH BIGMEM
-Semaphore bm version
The only difference a bigmem kernel can bring is more memory at the expense of 720p video recording. Playing a 720p video is still possible. Recording it is not on a bigmem kernel. Bigmem kernels normally have 13MB more than their non-bigmem counterparts. How this 13MB could affect you? It depends on the apps you use and how aggressive your LowMemoryKiller is.
XXJVT System apps
System apps can be frozen/removed to make your system faster/less battery draining.
In order to remove/freeze system apps, you would need Titanium Backup (Pro) or System Tuner.
The choice whether we want to remove or freeze the system apps should now be decided. Titanium Backup Pro and System Tuner uses a built in Android mechanism to freeze your system apps - PM disable. PM disable will actually disable the app from the system itself. It will not drain the battery or even launch itself. It is a safer way so to speak. Removing will physically delete the APK app from the system freeing up disk space. If you decide to remove, make sure to have a backup before proceeding. Even if you have a backup, restoring from Titanium Backup may sometime fail. Hence, do this only if you're sure you want to remove that certain app. Freezing an app will make it easier to defrost without any consequences.
Here are the apps that I disabled:
Code:
AngryGPS > Used to manually configure GPS. Not needed if GPS works OK.
BluetoothTest
Buddies Now
lcdtest
screencapture > Screen capture app
Daily Briefing
Days
EncryptApp
Factory Test
Gallery -> I use QuickPic as a replacement. It's faster than Gallery.
Google Partner Setup
Google Search > Google search widget
Home screen tips
HTML Viewer
Market Feedback Agent
Market Updater > I froze this to avoid being updated to Market 3.0. It currently sucks now
Mobile tracker > Mobile tracker, only if you use it, then keep it
Mobile tracker settings > Mobile tracker, only if you use it, then keep it
Perso
PhoneSetupWizard > Required if you're first booting/installing the ROM, not needed afterwards
PopupuiReceiver
Press Reader
Print via Bluetooth
RoseEuKor
Samsung Account
Samsung Keypad -> I use Swype beta instead
Self Test Mode
Service mode
SimDetachNotifier > Will notify you if you detached your sim card. Seems pointless
SNS > Only necessary to sync your contacts if you're using Social hub to do so or syncing calendar from Facebook
SNSAccount > Same as above
Social Hub
Software Update
Synchronise
TwLauncher -> Using Go Launcher Ex instead
wipeoutreceiver > Wipe if phone is stolen. Not needed if you don't use the Samsung service
WlanTest
wssyncmlnps
There are others that you can remove as well. I'm hoping to gather feedback on the other APKs that can be removed and what will be affected by its removal. Please post if you have more information
Disabling Lagfix
Most ROMs would advice you to disable lagfix before flashing a new ROM. Although this is not necessary in most cases (as all Gingerbread kernels support ext4 from the get-go) moving from one kernel to another might need it (to optimize the initramfs it is used on). Hence if you're swapping from one kernel (that has a different initramfs) to another. It is adviseable to undo the lagfix.
CF's lagfix can be undone by using the ext4 app.
Voodoo lagfix can be undone by using the Voodoo Control App.
Speedmod lagfix can be undone by using it's recovery.
Odexed ROM
You might say, hey if I'm using stock, I'll be missing extended power menu, battery percentage and all other theme mods that are not in the stock ROM. Fear not, you can get all these back including Gtalk2, CRT screen off etc here:
$omator's stock+
Gtalk2
There are odexed themes too, in which the developers would decompile the odex files into APKs, make the changes then compile the APKs into odex files again. It is more tedious than deodexed themes but odexing generally makes the phone smoother
You can find the themes here:
http://forum.xda-developers.com/forumdisplay.php?f=666
WIFI Issue on JVR/JVS/JVT
You might be facing some wifi connectivity issues on JVR/JVS/JVT ROMs i.e. it disconnects every few seconds.
This is due to some changes in the ROM that doesn't permit a "Forever" lease time from your modem. Change your lease time to an hour (or two) or if you don't have that option, remove your address reservation option from your modem (Yes, it's a modem only tweak, nothing you can do on your phone)
Memory Freak
Memory Freak is an app in TalonDev that tweaks the ZRAM/Swap and LMK settings. There's a golden rule to the ZRAM/Swap that is:
Swapping to and from the ZRAM will be slower if the amount of ZRAM is more than 50% of the total usable memory, . Hence, I set mine to 160MB (from the 340 total usable RAM). Swappiness in most Linux machines is 60. This means, the system will be inclined to swap in/out more than just using the RAM. I set mine to 50 as a personal preference so that there would be 50% chance that the system will use swap or RAM.
HiddenApp is the amount of free memory to be when LMK starts looking for hiddenapps to kill. I set mine to 52 for my multitasking preference. Experiment with it to see how much multitasking vs smoothness you're looking for. My preference will change in time. Check my signature for the most updated ones.
WIP:
This is obviously a work in progress article that will undergo changes as the Android scene improves. I will spend time to make edits and additions to the post whenever I see fit. Sometimes I will post changelogs at the end of the thread, sometimes I won't if I only make minor edits. Just be sure to check back often to see any new tips offered
Credits:
I claim no credit on these findings except for the ones that I've researched on my own. However, all of it is not of original work since I form my own opinions after reading a lot. I also don't claim that the settings I posted are the most optimal there is. It might not even work well for most of you guys. The key here is tweaking it to your own perfection as there is no setting that will cater to everyone's needs. Hence the real people who deserve credits are:
* All the devs' kernel/apps that I posted here
* XDA forum
* Google
Attention!
If you're looking for scripts, here it is:
[CWM][SCRIPTS][TWEAKS] Thunderbolt!
Script Reviews are here:
Script Reviews
GUIDE UPDATES
UPDATE 1/10/12
* Edited some sections with some new knowledge that I have. A few places, can't name them all Check them out and see if you can spot them.
UPDATE 10/19/11
* Moved around some guides and grouped them together
* Updated some guides to make them more Android centric (as opposed to i9000 centric)
UPDATE 10/18/2011 - Added an indepth article about LMK/OOM. CTRL-F for LMK.
UPDATE 10/12/2011
* Added some comments on the apps removed/frozen so that you can make an informed choice of why the apps can be removed/frozen.
* Added my analysis of most schedulers that I know of and why they are good/bad.
* Moved the scripts to ThunderBolt!: LINK
* Added a guide on the wifi issue for JVR/JVS/JVT
UPDATE 10/1/2011 - Moved the script reviews to this post LINK
UPDATE 9/23/2011:
* Removed the JournalingOn.zip and Acid Tweaksv6 - Removed Useless Stuff.zip because people might use it for devices other than the i9000. This is because in other devices such as SGS4G, the /dev/block/stl10 is /data while in i9000 it's /dbdata. The JournalingOn.zip will not enable journaling on /dbdata without some editing. Hence, I removed it as I don't have a time to put up a warning or notice, and didn't have time to edit the script inside the zip file.
* Readded an edited JournalingOn.zip and readded the Acid Tweaksv6 - Removed Useless Stuff.zip (did not change) to the first post. Only for i9000 devices!!
* Added another way to check if you're journaled or unjournaled. Check the guide below.
* Added some more explanation on common scripts I found.
* Moved the guides around due to lack of space. I added some minor changes to most of the guides. See if you can detect them
Helpful!
pikachu01 said:
Yes it is safe to remove for a deodexed ROM too
My point of stating odexed is that my tweaks can be used from the stock odexed ROM itself
Click to expand...
Click to collapse
oh ok, now I understand, thanks for this thread, very helpful indeed .
Awesome post thanks!
Not only for the tips but for teaching me a lot too!
Sent From My Android Shizzle!
thx dude!! awesomely useful!!
Great information thanks
Can you please include GPS tweaks as well?
awesomeandroid said:
oh ok, now I understand, thanks for this thread, very helpful indeed .
Click to expand...
Click to collapse
Thank you for reading it.
SkinBobUk said:
Awesome post thanks!
Not only for the tips but for teaching me a lot too!
Sent From My Android Shizzle!
Click to expand...
Click to collapse
It was my hope that it will give knowledge so that people could pass it on to more people
midikarma said:
thx dude!! awesomely useful!!
Click to expand...
Click to collapse
Thank you
ajazz said:
Great information thanks
Can you please include GPS tweaks as well?
Click to expand...
Click to collapse
Thank you for reading it What kind of GPS tweaks? There are a few notable ones. The most useful ones are disabling AGPS as well as updating the gps.conf. Do you mean that?
Oh man... Thx for your work... This thread is very useful.
I take my hat off.
Sent from nobody knows where
Wonderful job, pikachu01! A new user will need weeks, maybe months to gather all the bits of info you put here, served on a silver platter! Thank you veeeery much.
Mods, this should be stickied!
demonstone said:
Oh man... Thx for your work... This thread is very useful.
I take my hat off.
Sent from nobody knows where
Click to expand...
Click to collapse
Thank you
ZioGTS said:
Wonderful job, pikachu01! A new user will need weeks, maybe months to gather all the bits of info you put here, served on a silver platter! Thank you veeeery much.
Mods, this should be stickied!
Click to expand...
Click to collapse
Thank you Zio I forgot to add a few more posts to reserve. I guess I will add links if I do have any other things to add
Indeed lots of good info here for people just starting out, and some for people like me who've been around the block once or twice too!
I figured out how to do the CSC change myself, I just put the BMC folder from stock ROM into /system/csc and used one off the CSC selector apps from the market. Is this much different from the instructions here?
Since this has brought up the topic of freezing apps I will ask a question here if I may: Is there a way to keep apps from starting services, without getting rid of them? For example I use Skype and Facebook but I don't want their services running all of the time sucking up memory. Also I notice now that I game I installed recently (E Warriors) is running a service! WTF this is out of control. Any ideas?
haloimplant said:
Indeed lots of good info here for people just starting out, and some for people like me who've been around the block once or twice too!
I figured out how to do the CSC change myself, I just put the BMC folder from stock ROM into /system/csc and used one off the CSC selector apps from the market. Is this much different from the instructions here?
Since this has brought up the topic of freezing apps I will ask a question here if I may: Is there a way to keep apps from starting services, without getting rid of them? For example I use Skype and Facebook but I don't want their services running all of the time sucking up memory. Also I notice now that I game I installed recently (E Warriors) is running a service! WTF this is out of control. Any ideas?
Click to expand...
Click to collapse
Yes, the CSC instruction does the same thing. I'm just a bit thorough sometimes
You could use System Tuner or Titanium Backup Pro to freeze the app and then unfreeze it when you want to use it. Freezing is actually just doing a PM disable. PM disable basically makes Android think that the app is gone when it's actually still there. Unfreezing an app is basically just 1 click, hence its hassle free.
ZioGTS said:
Wonderful job, pikachu01!
Mods, this should be stickied!
Click to expand...
Click to collapse
Agreed +1
Excellent & informative
Awsome post pika.. Great work.. thx
Very nice tutorial. Should be pinned
Sticky please (with sgs chlorine).
Great work, much appreciated.
Sent from my Galaxy S using XDA Premium App
pikachu01 said:
Thank you for reading it.
It was my hope that it will give knowledge so that people could pass it on to more people
Thank you
Thank you for reading it What kind of GPS tweaks? There are a few notable ones. The most useful ones are disabling AGPS as well as updating the gps.conf. Do you mean that?
Click to expand...
Click to collapse
I have tried lot of Roms and none gave me satisfactory GPS performance except InnOvaTioN v2 by bezke,this Rom gave me almost instantaneous gps lock , when under partial cover it took a minute or so !
Then i moved on to v3 and was back to square one!
unfortunately v2 is no longer available for download.
I have tried Faster Fix, Gps Aids, tried changing setting through sgs tools but no go.
even tried different modems.
ajazz said:
I have tried lot of Roms and none gave me satisfactory GPS performance except InnOvaTioN v2 by bezke,this Rom gave me almost instantaneous gps lock , when under partial cover it took a minute or so !
Then i moved on to v3 and was back to square one!
unfortunately v2 is no longer available for download.
I have tried Faster Fix, Gps Aids, tried changing setting through sgs tools but no go.
even tried different modems.
Click to expand...
Click to collapse
well, then open a thread on general, Q&A, etc.
and let someone upload it
hopefully there are still copys of it out there
so there's a way to analyze and understand what was done to get those great results
@pikachu01:
great work on collecting all of this information & putting it in a central place !
*subscribes*
+1 for sticky
Very nice guide. It'll be very helpful for begginers. +1 for the idea to stick it