[Q] Using ext4 Journalling System - Tilt, TyTN II, MDA Vario III Android Development
I've been seeing more and more android builds switching to ext4 (iDroidProject included) journalling system. Does our 2.6.32 kernel support ext4, and if not is there a way to include it in the kernel build?
Reason I'm asking is from what I'm understanding the ext4 journalling system could solve alot of issues in terms of data corruption, and slowness?
I see that the Gingerbread devices have this by default, but from what I understand, the kernel is the one that needs to support this, not the OS.
I would like to hear your thoughts on this, as I'm completely unfamilar with this area. lol
Krazy-Killa said:
I've been seeing more and more android builds switching to ext4 (iDroidProject included) journalling system. Does our 2.6.32 kernel support ext4, and if not is there a way to include it in the kernel build?
Reason I'm asking is from what I'm understanding the ext4 journalling system could solve alot of issues in terms of data corruption, and slowness?
I see that the Gingerbread devices have this by default, but from what I understand, the kernel is the one that needs to support this, not the OS.
I would like to hear your thoughts on this, as I'm completely unfamilar with this area. lol
Click to expand...
Click to collapse
Same here, would like to know,
Prowess said:
Same here, would like to know,
Click to expand...
Click to collapse
Ext4 can be added in our kernel, I initially thought that this filesystem is for external memory and not applicable for NAND but if they are doing it with IDROID then I think we need to edit our init to support this + support for the kernel. Is there full support for ext4 on NAND? Can you give us a link?
ext4 has a high number of writing cycle so the nand will be destroyed very fast.
For the same reason it isn't enabled for sd.
l1q1d said:
ext4 has a high number of writing cycle so the nand will be destroyed very fast.
For the same reason it isn't enabled for sd.
Click to expand...
Click to collapse
That part may be true, and if that were the case. Then the benefit must outway the cost, especially if its being used for the iDroid for the older iPhone and 3G models which have been around for probably as long as our Kaisers.
Plus hasn't flash memory evolved even in older devices like ours to handle over a billion (probably exagerating on this) writes in its lifetime?
Hell USB flash drives are now used as removable RAM sticks on modern computers and laptops, plus used in bootable media like Linux/Ubuntu.
And also as you stated ext4 uses A LOT of write cycles right? Then why are the newer Androids using ext4 if it'll destroy the NAND very quickly?
Sent from my AT&T Tilt using XDA App
I still wouldn't push it. Most of us have bad blocks on our NAND already.
aceoyame said:
I still wouldn't push it. Most of us have bad blocks on our NAND already.
Click to expand...
Click to collapse
Well, hate to say it but from what I'm seeing here is almost exactly like what happened when the NTFS system was released for NT4. A lot of people complained that it would destroy older drives, with its higher write and read cycles. Granted this is completely different than hard drives, but too me feels the like the same situation almost 12 yrs ago.
I'm just saying what's the harm of putting it in the kernel and warning people of the potential risks involved (as always lol).
Hell isn't having Android on the Kaiser a risk anyways?
Sent from my AT&T Tilt using XDA App
Krazy-Killa said:
Well, hate to say it but from what I'm seeing here is almost exactly like what happened when the NTFS system was released for NT4. A lot of people complained that it would destroy older drives, with its higher write and read cycles. Granted this is completely different than hard drives, but too me feels the like the same situation almost 12 yrs ago.
I'm just saying what's the harm of putting it in the kernel and warning people of the potential risks involved (as always lol).
Hell isn't having Android on the Kaiser a risk anyways?
Sent from my AT&T Tilt using XDA App
Click to expand...
Click to collapse
Thats the thing though, i've actually killed a flash drive by reaching the max # of Read and Write cycles. For our nand's to be getting bad blocks means they have around a few years left as it is. I can't imagine what EXT4 would do to it lol. Also people who said that for hdd's must not know that hard drives include extra sectors. On our drives it just wear levels and marks the blocks bad as they go. It has no extras.
No hard drive has extra sectors. Hard drives rely on magnetism for their data entry of 1s and 0s, where as flash drives use electrical switches. Both have the same problem of bad sectors/blocks -- hardware failure.
If a hard drive sector fails, it's gone. No extra sector to replace it. Same with flash drives.
If sector 0 on a hdd were too fail, the drive fails entirely, because the BIOS reads sector 0 for the bootloader. What you're saying is if sector 0 failed a backup sector would replace, which has never happened in my 12 yrs of computer repair.
Sent from my AT&T Tilt using XDA App
Krazy-Killa said:
No hard drive has extra sectors. Hard drives rely on magnetism for their data entry of 1s and 0s, where as flash drives use electrical switches. Both have the same problem of bad sectors/blocks -- hardware failure.
If a hard drive sector fails, it's gone. No extra sector to replace it. Same with flash drives.
If sector 0 on a hdd were too fail, the drive fails entirely, because the BIOS reads sector 0 for the bootloader. What you're saying is if sector 0 failed a backup sector would replace, which has never happened in my 12 yrs of computer repair.
Sent from my AT&T Tilt using XDA App
Click to expand...
Click to collapse
They do have extra sectors for re-allocation. Well it won't recover the data of course but it would still be able to use it for data, it would mark it as bad and use a spare. When you partition a drive it doesn't use 100% of the sectors on the drive, more like 99.75% of them. Your right about the sector 0 thing. Although it has the extra sectors it doesn't mark it as sector 0. It basically just allocates the extra sector for use but to use it you would have to repartition the drive so it can use it.
See http://en.wikipedia.org/wiki/Bad_sector
If you want you can see how many spare sectors have been used by checking your drive's SMART status with speedfan under the reallocated sector count field.
I have less official experience but I built my first computer when I was 7 with assistance from my father, I am 20 years old, will be 21 in a couple weeks and I have been in the field roughly 3 years now. I only know stuff like this since I read articles about computer hardware alot lol.
Well anyways, ill take a look, but on my phone with no access to a PC atm.
Back on point, lol. From what I'm understanding if we were to switch to ext4 it would increase write cycles, decreasing NAND life.
But with the ext2 setup we have massive corruption no matter what we do. Which means we have to install Android constantly, which based on how many files are in /system, would increase write cycles briefly but exponiently because were writing to NAND on a grand scale, and plus with constant kernel flashes to update and hope for fixed corruption.
If ext4 really does help or even solve these corruptions it would mean less android re-installs, less data restores. Plus more in-frequent kernel updates, which will reduce write cycles anyways.
Plus if there is a performance gain, it would further reduce write cycles.
Am I right on this?
Sent from my AT&T Tilt using XDA App
I thought our NAND FS was YAFFS? EXT2 was only for SD if I recall. Faster speed doesn't mean less disc access, just means it is doing them faster. The only thing that would help is battery life as the cpu will be sitting idle more.
Oops yah meant YAFFS. I'm still on the iDroid mind set. They were using ext2 I believe, and recently switched to ext4 with their Gingerbread release.
Granted they use images inside the NAND, but that would still be the same thing regardless once the kernel is loaded.
What about YAFFS for /system and ext4 for /data. The kernel has that capability right?
Sent from my AT&T Tilt using XDA App
It should have that capability but I would really only use EXT4 on an SD card. YAFFS is the best choice for our kaisers right now since it is designed for NAND gate storage, whereas EXT4 is just a generic all purpose journaling filesystem.
The only problem with YAFFS is we didn't have the latest version for awhile and now we just have to figure out wtf were doing and get it configured right. There are a lot of variables that can be set.
Are we using YAFFS or YAFFS2? Both are designed for a specific NAND. Which one does our Kaiser fall into?
Sent from my AT&T Tilt using XDA App
hai there...
sorry to interupt u guys..
NWY,if there is time that when ext4 are available with system on SD as i saw that ext4 with data have are already looking great,could u guys make it for HARET as I'm lately using haret alot..
its a huge appreciation if anyone of u could do it...
thanks
Related
So I have this idea....
Hi guys I'm not a programmer by any means, nor do I know anything about developing software, so take this idea with a grain of salt. The issue I notice from time to time with my PPC6800 is slowdown from lack of ram (or that I haven't closed the apps and they're hogging the ram). My phone only has 64mb....so this got me thinking.... Vista has a feature called Readyboost which uses any flash based USB key to act like virtual ram (or a pagefile). SO, how feasable would it be to create software that would coule read/write off the microSD card as if it were ram? Basically a MobileReadyboost as it were. Discuss amongst yourselves =) PS: Forgive me if something like this already exists for our platforms...but I haven't seen it.
SD cards read and write slow... What if deleating the extended rom partition (located in ram, right?) and using that for a pagefile instead? most people don't seem to use the extended rom when cooking. why not just make it usefull?????!!!!!
S.V.I said: SD cards read and write slow... What if deleating the extended rom partition (located in ram, right?) and using that for a pagefile instead? most people don't seem to use the extended rom when cooking. why not just make it usefull?????!!!!! Click to expand... Click to collapse SD cards can be slow, but there are some models that are faster. Granted they cost more and are a little harder to find, because they are aimed photo people. But yeah.
extended rom in cooked roms is generally used for extra storage anyway so it isnt like it isnt being used
"SD cards can be slow, but there are some models that are faster. Granted they cost more and are a little harder to find, because they are aimed photo people. But yeah." problem is that today it's not just sdcards which is the bottleneck the sd interface itself on the cpu is slow too
EXT4 Journaling On vs. RFS (Journaling On by Default)
Hello, I am currently using a Rom with EXT4 and No Journaling and am experiencing Data Corruption. I want to switch to a ROM capable of Journaling. What is the difference between RFS and EXT4 with journaling on? And will EXT4 with journaling significantly impact my Phone writes so the internal drive fails faster than RFS? Thanks I read this article and saw that EXT2 is much more efficient for SGS Devices, why not use that instead of EXT4? http://hkdennis2k.homeip.net/2010/11/04/reality-behind-rfs-lag-of-samsung-galaxy-s/
This debate raged a while ago when devs first began introducing ext4 into their roms. I can answer some of your post by saying that ext4 organizes your files much more efficiently for our flash based storage. RFS essentially treats storage like it is platter based (like a hdd). Without getting into much detail, ext4 locates and organizes data better than rfs. Ext4 is still better, even with journaling on.
but I heard that after about a year, the drive will fail due to too many read and writes because of EXT4 with journaling on. Is that true?
gokuman56 said: but I heard that after about a year, the drive will fail due to too many read and writes because of EXT4 with journaling on. Is that true? Click to expand... Click to collapse I'm not sure anyone really knows how long the drive will last. I'm sure it's way longer than a year. It will defiantly outlast your contract with Sprint.
It will definitely outlast your Sprint contract. And it's likely that it will not have any effect on your memory blocks at all. Noobnl had a thread a while back where users ran a test of their memory blocks. Many users that have been using ext4 for months and had flashed roms to their phones multiple times (I.e. 10x, 20x 30x). There was no increase in bad blocks at all over a few months of use. Our phones' storage operates just like a ssd on computers. Sure there will be wear but we are talking about 100k+ write cycles. I wouldn't worry at all about it.
[Q] ext3 or ext4; ext4 shorter lifetime?
Hi, first-time-rom-installer here so bare with me if I'm asking stupid questions I followed http://forum.xda-developers.com/showthread.php?t=1016084 so far with success, I've just finished partitioning the SD card but then I accidentally read something about ext4 would cause a shorter SD lifetime. I'm not up to speed on all this stuff so logically I would go for ext4 (newest technology) but seen a lot of people saying there isn't noticable difference between ext3 and 4 is it really worth reducing SD lifetime? Thx! B
could you show us the info about ext 4 shortening lifetime
This shorting lifetime is a load of bull **** lol I have never seen one good evidence to this
I guess these are theories. I know leedroid has mentioned it.
Internal SD card question
Hi, I just got a brand new Galaxy Nexus and I wanted to ask about the internal SD card. It is to my understanding that normal SD cards die over time with use (if you keep copying files on and off it). I want to watch heaps of videos on GNex and I was wondering if the internal SD would 'die' quicker if I kept on copying video files onto it over and over again. Thanks for any help. -FireStampler
Its not an internal SDcard, its a virtual path on the internal storage that's an "SDcard". I highly doubt you'll ever read/write enough on the flash storage to negatively affect it in the phone's lifecycle.
martonikaj said: Its not an internal SDcard, its a virtual path on the internal storage that's an "SDcard". I highly doubt you'll ever read/write enough on the flash storage to negatively affect it in the phone's lifecycle. Click to expand... Click to collapse Challenge Accepted... just kidding, Thanks
Theoretically, yes. And I actually posed the same question about Swap and Zram to my Kernel Developer. I got a fairly long post about how (again, theoretically, yes) it may impact after years of use...but not to the extend that I shouldn't be able to complete my two year contract or anything similar. While this was my original assumption, the reassurance felt nice. That...and have you ever had an SDcard **** out on you? I never have. Nor have I heard of it happening to anyone I know (aside from 1/100000000 people online...you know). Tl;DR Writing constantly to the internal storage CAN impact performance negatively. But it'd be an extreme case to have this impact you during the years that you own the device.
If I'm not mistaken, current generation MLC NAND starts to degrade after around 10,000 writes cycles, so that should last you quite a while .
Jubakuba said: ...That...and have you ever had an SDcard **** out on you? ... Tl;DR Writing constantly to the internal storage CAN impact performance negatively. But it'd be an extreme case to have this impact you during the years that you own the device. Click to expand... Click to collapse No but a friend who does photography has had a 2gb one die a while back and I've had a mechanical hard drive (although this is totally different to flash storage ) crap out on me just a few days ago. This is my first smartphone so I want to be cautious but I also didn't buy it just so it would sit there doing nothing Thanks for your advice, hope I can make this phone last a few years.
[Q] How increase RAM in JB..??
Hi All after upgarde from GB to JB (either LEAK / Official), JB seemed Slow. whether to change the partitions on a flash PIT file MB2 / 4 can increase the RAM capacity in JB. I found a thread where we can change it by using the application PIT "PIT_Magic". but I do not understand how its use. if anyone can to using it please share... Thanks Original Thread PIT MAGIC
rozyid said: Hi All after upgarde from GB to JB (either LEAK / Official), JB seemed Slow. whether to change the partitions on a flash PIT file MB2 / 4 can increase the RAM capacity in JB. I found a thread where we can change it by using the application PIT "PIT_Magic". but I do not understand how its use. if anyone can to using it please share... Thanks Original Thread PIT MAGIC Click to expand... Click to collapse You cant do that!there is about 140MB unused ram in stock firmware. in order to increase ram and use full of it ,you sould have uncompiled kernel source and know android kernel programming and change it. but always you can change your phone partition sizes through PIT Magic while falshing.
kernel source sorset said: You cant do that!there is about 140MB unused ram in stock firmware. in order to increase ram and use full of it ,you sould have uncompiled kernel source and know android kernel programming and change it. but always you can change your phone partition sizes through PIT Magic while falshing. Click to expand... Click to collapse Hi Sorset maybe we can help to hafidzduddin to edit the kernel in order to read that we change the RAM to 1 GB .. ..
From where you flashing JB? From GB or JB XXMB4?
edit PIT to get 1gb RAM ddikodroid said: From where you flashing JB? From GB or JB XXMB4? Click to expand... Click to collapse from JB MB4 i just Edit PIT FILE on MB4 to get RAM 1 GB, but I have not dared to try it.. I am still gathering information about the RAM partition address....
1 GB? ~768MB is enough for me. Though i really think that it can't go over 700+MB.
1 Gb? WTF? Our device doesn't have true ram? I thought that we have some sort of LDDR2 ram and it's quite different from it's flash NAND. I think you can't go over installed 768 mb and you can't even reach this number because gpu also use the same ram. I hope Samsung didn't put the ram on storage because it will wear out like hell. NAND it's not fast, not even prone to multiple write cycles. Even if you're successful in increasing you ram, you will make something like swap partition on linux. But I highly doubt it will work. Swap system is not used on mobile devices because NAND wears up too fast.
According to this: http://forum.xda-developers.com/showpost.php?p=35222874&postcount=14 ...we do not have LDDR2. There is only 4GB chip named UME300 (IC-NAND Flash Memory, 4 GB, SDIN5D2-4G-944L, BGA, P/N: 1107-002091) It may be true regarding memory size of ACE 2: system 1,2 + USB 1,1 + 0,768 + spare for dead cells = 4GB SIII Mini for example have 1GB RAM and I/O and RAM operations are much much faster. Also there are no 768MB LDDR2 chips on market. Using emmc as low speed LDDR2 substitute is quite common in Samsung devices.
arroyo said: According to this: http://forum.xda-developers.com/showpost.php?p=35222874&postcount=14 ...we do not have LDDR2. There is only 4GB chip named UME300 (IC-NAND Flash Memory, 4 GB, SDIN5D2-4G-944L, BGA, P/N: 1107-002091) It may be true regarding memory size of ACE 2: system 1,2 + USB 1,1 + 0,768 + spare for dead cells = 4GB SIII Mini for example have 1GB RAM and I/O and RAM operations are much much faster. Also there are no 768MB LDDR2 chips on market. Using emmc as low speed LDDR2 substitute is quite common in Samsung devices. Click to expand... Click to collapse I thought this was a joke at first when rozyid said we can increase our RAM so it was 601MB system + 302MB cache + 1,2GB data + 1,1GB usb = ~3,2GB It will make sense if the remaining is our "RAM" if somehow someone able to increase this by resizing other partition (/cache maybe?) it would be really nice And btw, what is the function of /cache? When I checked it using link2sd it wasn't used But hey, didn't we used another partition /preload in JB? If I'm not wrong it was about 200MB, right? So then it be more than 4GB if we add it to previous calculation Sent from my GT-I8160 using xda app-developers app
[Noob] For example wont decreasing the RAM on the device increase the "ram" allocated to the GPU thus increasing our gaming performance in any way?
S3 mini RAM score is only 10% faster in antutu, either S3 mini doesn't have true RAM or our device has one.
I think you've added up incorrectly here. 4GB is usually 3.7gb total. Also, if you looked in the PDF's from one of the links above, you would notice we do in fact have LP-DDR2 ram...
arroyo said: According to this: http://forum.xda-developers.com/showpost.php?p=35222874&postcount=14 ...we do not have LDDR2. There is only 4GB chip named UME300 (IC-NAND Flash Memory, 4 GB, SDIN5D2-4G-944L, BGA, P/N: 1107-002091) Click to expand... Click to collapse I was very confused when you wrote this. It's absolute non-sense to use NAND as RAM. It will wear in only one month. They should have at least the most creepy ram, cache or something else that it can be re-writable. You can have smooth gui with no RAM installed. It's impossible. You can't draw 20000 triangles per frame and having decent framerates without having a ram that it's capable of speed near 1 Gb/s ... Also usually memory came in banks, 256 Mb banks were usual in the past, so puting 3 banks can give you 768 MB.
@Jamielawther I would love that fact to be truth, but this diagram is not hardware schematic. It is logical diagram how things push data between elements. Move couple pages further and try to find element for LP-DDR2 on PCB. I did not found one. Also in document 05-GT-I8160-EPLIS-11.pdf you have the list of electrical parts. I did not found SEC Code for anything that could be LP-DDR2. @veaceslaw Take a look at PCB in 08-GT-I8160-TSHOO-7.pdf. There are no 3 ram chips there. In fact there is only one 4GB. If they used emmc as a RAM, it won't die in one month. Probably it last for 2 years or more ... after warranty it may die. In my PC, SSD disk is used as TEMP and cache memory for last 2 years. Still running flawlessly. Every ROM chip has some space left for spare blocks to be used as a replacement for died blocks.
arroyo said: @veaceslav Take a look at PCB in 08-GT-I8160-TSHOO-7.pdf. There are no 3 ram chips there. In fact there is only one 4GB. If they used emmc as a RAM, it won't die in one month. Probably it last for 2 years or more ... after warranty it may die. In my PC, SSD disk is used as TEMP and cache memory for last 2 years. Still running flawlessly. Every ROM chip has some space left for spare blocks to be used as a replacement for died blocks. Click to expand... Click to collapse Can you find the U8500 chip?
veaceslav said: Can you find the U8500 chip? Click to expand... Click to collapse UCP300
arroyo said: UCP300 Click to expand... Click to collapse http://forum.gsmhosting.com/vbb/archive/t-1363562.html UCP 300 is RF chip and I don't know what rf is, but it's in GT i9100 and I don't think i9100 have Novathor
if you do it guys it would be awesome because all good games with best graphics lags i even dont want to get back to this ugly outdated gingerbread
arroyo said: @Jamielawther I would love that fact to be truth, but this diagram is not hardware schematic. It is logical diagram how things push data between elements. Move couple pages further and try to find element for LP-DDR2 on PCB. I did not found one. Also in document 05-GT-I8160-EPLIS-11.pdf you have the list of electrical parts. I did not found SEC Code for anything that could be LP-DDR2. @veaceslaw Take a look at PCB in 08-GT-I8160-TSHOO-7.pdf. There are no 3 ram chips there. In fact there is only one 4GB. If they used emmc as a RAM, it won't die in one month. Probably it last for 2 years or more ... after warranty it may die. In my PC, SSD disk is used as TEMP and cache memory for last 2 years. Still running flawlessly. Every ROM chip has some space left for spare blocks to be used as a replacement for died blocks. Click to expand... Click to collapse Anyone bothered to look through the documentation? If you check 08-GT-I8160-TSHOO-7.pdf on the first page you can see the block diagram and there you can see stated LP-DDR2. Check the attached picture.
If same chip is being used as RAM, then what is the benefit of moving data from on part of same memory to another? Won't that reduce io speed, cos I thought the purpose of RAM is to speed up data access for CPU from normally slower data storage eg. Hard drive. Sent from my GT-I8160 using xda app-developers app