Develop Bugs

Using fast SD cards?

I see these 66x superfast SD memory cards advertised. Will using one speed up my blue angel?
Can programs use this SD card for operating memory or can they only use the intenal memory?
Does having <5mb avaialable slow down your device?

Fast Sd Cards
Fast Sd cards are only useful for SLR Pro cameras. The rest of the devices are using normal card reader slots. i.e. even if you were to use a fast SD card in the sd card slot,you will only get the normal speed.
by rest of the devices, i mean, all pocket pcs, ppc phones, phones and such devices...... :x

moali77 is correct. it won't make much of a difference in your pda. however, if you use a card reader, or happen to have a digicam that can utilize the speed, you will be better off.
example: i played atlantis redux recently 100mb+ required to be put on your sd card. instead of copying it through activesync, i put it in my usb2.0 card reader, copied it over, in far less time than it would've taken if i did it the other way.
but if you don't plan for much of that, then don't bother paying the premium for a fast card =)

Well I bought a Kingston Elite Pro Secure Digital 1GB, think It's 7.7/8.2MB Write/read
It made my TomTom go way faster planning routes and generally give me better performance from other apps.
I dont know the Top speed for the BA SD Slot, but you should look at the speeds of the card you are planning to buy

bosjo said:
Well I bought a Kingston Elite Pro Secure Digital 1GB, think It's 7.7/8.2MB Write/read
It made my TomTom go way faster planning routes and generally give me better performance from other apps.
Click to expand...
Click to collapse
Have others experienced similar variations with different SDs?

I recently responded to Wamatt's other posting about SD cards in the BA accessories forum. In it, I've described my experiences with the SD card listed in my sig and BA speed tests I've done with it.
See http://forum.xda-developers.com/viewtopic.php?t=26903 for additional information.

Some questions about micro SD

Hi guys, I have a few questions about micro SD:
1) Does higher class drain more battery?
2) I just purchased a LG optimus 2x, is a class 6 enough for me? or do I need to go all the way to class 10?
3) Will higher class cause lagness to the phone?
Thanks guys

akira de aimbuster said:
Hi guys, I have a few questions about micro SD:
1) Does higher class drain more battery?
2) I just purchased a LG optimus 2x, is a class 6 enough for me? or do I need to go all the way to class 10?
3) Will higher class cause lagness to the phone?
Thanks guys
Click to expand...
Click to collapse
1. From what I've seen, it seems some higher class cards drain battery more... I think the brand and quality of chips make more difference with battery, though.
2. Is class 6 enough for what? What are you using the card for? If it's strictly for taking pictures or videos, or transferring large files, or other tasks that you only need sequential write and reading, then higher class would be quicker for that. But class 6 is pretty quick with sequential reading/writing... it's up to you if you need higher. What are you using the card for?
3. Yes, higher class cards can cause lagness if you have apps or OS files on it, or if the phone is trying to access many different parts of the card quickly. Generally, for using with a phone, you will get better performance with class 2 or 4 cards. Higher class cards generally have slower access times and slower random access speed and random read and write speeds. Class 6 and 10 are better for digital cameras, or for transferring large files, but for use with a phone, where you may run apps off it or have the OS trying to access many bits of data from different parts of card, class 2 or 4 usually perform better there.

zarathustrax said:
...Yes, higher class cards can cause lagness if you have apps or OS files on it, or if the phone is trying to access many different parts of the card quickly. Generally, for using with a phone, you will get better performance with class 2 or 4 cards. Higher class cards generally have slower access times and slower random access speed and random read and write speeds. Class 6 and 10 are better for digital cameras, or for transferring large files, but for use with a phone, where you may run apps off it or have the OS trying to access many bits of data from different parts of card, class 2 or 4 usually perform better there.
Click to expand...
Click to collapse
Can it be true; I suspect the "slower access times and slower random access speed and random read and write speeds" coming from higher class (10) microsd cards have to do also with bad quality, cheap (see chinese) chips that hit the market with the class 10 hoax. I hope "serious" manufacturers will produce cards that could achieve not only sequential, but also satisfactory random speeds.

Are there any sites that rank microSD cards based on random access time?
THG has some data for miniSD cards but most other sites have scattered reviews and no direct ranking.

me00016 said:
Can it be true; I suspect the "slower access times and slower random access speed and random read and write speeds" coming from higher class (10) microsd cards have to do also with bad quality, cheap (see chinese) chips that hit the market with the class 10 hoax. I hope "serious" manufacturers will produce cards that could achieve not only sequential, but also satisfactory random speeds.
Click to expand...
Click to collapse
Well there are quality cards that do good at both... a Sandisk class 4 is one of the best all around I've seen. It pretty much gets class 6 sequential write speeds, and still has great access time and random speeds.
But the lag cause by class 10's and 6 isn't only because of low quality... it's caused because the higher class chips are designed to initialize the part of the card it's about to use, which gives much better sequential speeds, but hurts the access time and random read and write where many parts of the chip are accessed quickly getting small bits of info in many different parts. In this case, the initialization that the chip is doing causes it to take much longer, as it still initializes each part before accessing it. That extra step it's doing adds up to a lot of extra time when its using lots of random parts of the chip to read or write only a small bit of data.
Cards that don't do this initialization and just begin accessing immediately is obviously going to be quicker when using many different parts of card.

zarathustrax said:
2. Is class 6 enough for what? What are you using the card for? If it's strictly for taking pictures or videos, or transferring large files, or other tasks that you only need sequential write and reading, then higher class would be quicker for that. But class 6 is pretty quick with sequential reading/writing... it's up to you if you need higher. What are you using the card for?
Click to expand...
Click to collapse
Most probably I will dump everything into the card, reading games from it, using gps with map files inside the sd...etc. So I guess a class 6 is sufficient. But now people are telling me even class 4 is sufficient, while some say that they observed huge different from class4 vs class 6, I got confused
May I know if android is using sequential access or random access? Or is it depends on the software?

akira de aimbuster said:
Most probably I will dump everything into the card, reading games from it, using gps with map files inside the sd...etc. So I guess a class 6 is sufficient. But now people are telling me even class 4 is sufficient, while some say that they observed huge different from class4 vs class 6, I got confused
May I know if android is using sequential access or random access? Or is it depends on the software?
Click to expand...
Click to collapse
I'm confused too, after 2 months trying to find the optimum 32gb microsd for my SGS. Well, the thing gets complicated (especially for 32gb capacities) because of many reasons:
- Inconsistent quality assurance-high percentage of defect cards, sometimes of the same lot, even from top brands. This could be not only a non working card, but also small but critical problems like write failure, freeze, etc.
- Users, we don't know what we want microsd for; surely we all want to upgrade the memory of our phones, but it seems that others don't like to wait long transfering 1080p movies in the device, others want to use app2sd with android. I've come to the conclusion that right now in the market there is not a product that can do all jobs satisfactory (maybe Sandisk c4?).
- Fake cards.

What is difference in SD card classes

Ok I have an Acer Iconia a500, currently I have only a 6gb card installed. Now when i look online i see that the micro sd cards are rated by classes. What is that for?
I need a 32gb for my Iconia. I do alot of school work from it. Just want the storage for my school books. any way, can someone break it down for me?
Thank You
Sent from my A500 using XDA Premium App

The SD card's class represents the least write speed.
Class 2: 2MB/s
class 4 : 4MB/s
and so on..

I think it's so you can copy and read files faster

ok, got it, higher the class the faster the write speed.
One more thing, now, the higher the class, does anyone know if they have more problems? like with crashing, or having to be re formatted often?

primus123 said:
ok, got it, higher the class the faster the write speed.
One more thing, now, the higher the class, does anyone know if they have more problems? like with crashing, or having to be re formatted often?
Click to expand...
Click to collapse
Nope, problems/crashing etc would be down to quality not size.
Also faster write speed doesn't mean it performs faster when used as a "hard drive" like in a phone, so lower class ones can outperform higher, but you'd have to try them to see.
It's because they're designed with things like cameras in mind, where getting the image saved quickly so you can take another one is the most important thing.
In a mobile phone/tablet they're accessed more randomly, and that is where it's been found that some higher class cards don't perform as well.

Mini SD cards, so tiny for my big hands.
Those mini sd cards are SOOOOO small, I've lost a few over the past 3 years.

so which one should i get for my iconia

androidappdeveloper said:
Those mini sd cards are SOOOOO small, I've lost a few over the past 3 years.
Click to expand...
Click to collapse
Tell me about it, I just reordered one after giving up the search on my current one. It's not completely lost, I'll probably come across it one day when re-organizing the room.

I keep mine in those Sd card cases and shove it in a crown royal bag....

You're probably fine with a Class 2 microSD card, as you won't have large files (or a large amount of small files) written in a short time.

Write speeds are generally the most important feature of a memory card. Write speeds determine the amount of time it takes to transfer the data, the moment you for example, click the button on your camera to ask the camera to take the image. You will probably remember that back in the early days of SD memory cards, there was an awful amount of lag time on cards, i.e from when you heard the click on the button (when you asked your camera to take the picture), to when you heard the double click (which is normally when the image has been written to the card).
Read speeds indicate the amount of time it takes for a card to transfer the data to a PC/Laptop. I.e the amount of time it takes to read the data off the card. Generally the higher the capacity of the card, this will naturally give a higher write speed. So if you have a 32GB card full of data and its only a class 2, it would take much longer than a 32GB card thats class 10, to send all the info to your pc etc.
Class 10 cards are recommended for HD video, or minimum class 6 really. You will probably find a 16GB class 4 card for example, will not work on say a Samsung HD Camcorder. It will maybe store only 1 minute of video, as for some reason the HD cannot write the data to the card fast enough it would seem.

Anyone ever lose a mini SDK card?

Plus your SD class is high, more it is fast...

jerryfranks said:
Anyone ever lose a mini SDK card?
Click to expand...
Click to collapse
Yes, almost (I found it after w hile), bloody spring so strong it shot across the room!
Pity there's not some little leatherette folder with tiny slots for a few MicroSD cards, I'd buy one!.

iloveapple said:
Write speeds are generally the most important feature of a memory card. Write speeds determine the amount of time it takes to transfer the data, the moment you for example, click the button on your camera to ask the camera to take the image. You will probably remember that back in the early days of SD memory cards, there was an awful amount of lag time on cards, i.e from when you heard the click on the button (when you asked your camera to take the picture), to when you heard the double click (which is normally when the image has been written to the card).
Read speeds indicate the amount of time it takes for a card to transfer the data to a PC/Laptop. I.e the amount of time it takes to read the data off the card. Generally the higher the capacity of the card, this will naturally give a higher write speed. So if you have a 32GB card full of data and its only a class 2, it would take much longer than a 32GB card thats class 10, to send all the info to your pc etc.
Class 10 cards are recommended for HD video, or minimum class 6 really. You will probably find a 16GB class 4 card for example, will not work on say a Samsung HD Camcorder. It will maybe store only 1 minute of video, as for some reason the HD cannot write the data to the card fast enough it would seem.
Click to expand...
Click to collapse
Very helpfully post,thanks.
Sent from my GT-I9000 using Tapatalk

Try to continue promoting of you site.

Hi speed cards are more efficient at presenting and recording. It's really up to you. If you buy the cheaper version and it doesn't present at the speed you think it should you'll have answered your own question.

You guys have it mostly right. The higher class your card is the faster it can write a file to its memory, the trade off is that the higher class cards have slower rapid access speeds, something to do with how it prepares files before writing. Basically, a class 10 will write a 1GB file faster, but if you try to write 15 3MB files quickly your performance will suffer. For something like a phone I recommend a class 4 or 6. For cameras I'd go higher (I don't know a whole lot about cameras).

seems like its good

[Q] Dalvik Cache

By moving the dalvik cache to the sd-ext, does it slow the rom down?

Some people will say yes, some people will say no...
From personal use I'll say I've moved my dalvik cache to my sd card on a couple of rom's and never noticed a difference. I wouldn't recommend it with a class 2 sd card, but with class 4 and above it should be fine.

I never felt any difference and I have been practicing this long before alternate hboot's came into play.
Also card's wear is reduced and supposedly battery life a bit better by a marginal value equal to those of havs/svs, hardkeys backlight on/off etc.
zedmarcus said:
I wouldn't recommend it with a class 2 sd card, but with class 4 and above it should be fine.
Click to expand...
Click to collapse
Again:
Class = minimal sequential write speed -> large files.
Random writes -> dalvik cache.
Hence, cards class only guarantees card will perform at it's rated speed with sequential writes. Unfortunately increase in sequential speed doesn't mean linear increase in random. Or put bluntly, this justifies why some people could run data2sd scripts with lower end cards better than the others who had better cards.

erklat said:
I never felt any difference and I have been practicing this long before alternate hboot's came into play.
Also card's wear is reduced and supposedly battery life a bit better by a marginal value equal to those of havs/svs, hardkeys backlight on/off etc.
Again:
Class = minimal sequential write speed -> large files.
Random writes -> dalvik cache.
Hence, cards class only guarantees card will perform at it's rated speed with sequential writes. Unfortunately increase in sequential speed doesn't mean linear increase in random. Or put bluntly, this justifies why some people could run data2sd scripts with lower end cards better than the others who had better cards.
Click to expand...
Click to collapse
Saw you having a similar conversation with island3r in the insertcoin thread
AGAIN: "http://www.tomshardware.com/reviews/...i,2940-11.html
Scroll down to sequential write. As the class goes up (in direct relation to the card's brand quality) sequential write speeds go up as well.
Of course, for instance, a Kingston class 6 is going to be faster than a Adata class 10.
But as a general rule (especially between the same brand), the higher the class, the higher the speed."

This time I am better prepared, second. Couldn't find it last night for the love of God otherwise that argument would be over quickly.
EDIT:
sibere said:
Card class indicates minimum sequential write speed achievable on the card.
It's good for writing big files like movie files.
But when it comes to writing small random files, it can be the opposite. Many people reported having bad random write speeds with C10 cards whereas others reported better speeds with lower class cards.
It's a matter of sd controler quality and size of erase block size. Bigger and faster SD cards have bigger erase block sizes (up to 256Ko). It means that those cards need to write 256Ko of data even for writing a single byte on the card.
That's why C10 are not the best choice when it comes to DATA2SD or any kind of similar solution to short data storage on the Desire.
Click to expand...
Click to collapse
Now, I don't suppose that creator of data2sd scripts knows anything better than island3r or Tom's hardware, but that's just the way it is. Your choice whom are you going to take for serious.
I suppose you are going to start rant about 720p recording in dalvik thread like he did?

Thanks for the replies. But I think i will leave it where it is on the internal memory because my SD-ext is only 512mb and I am running out of space

erklat said:
This time I am better prepared, second. Couldn't find it last night for the love of God otherwise that argument would be over quickly.
Now, I don't suppose that creator of data2sd scripts knows anything better than island3r or Tom's hardware, but that's just the way it is. Your choice whom are you going to take for serious.
I suppose you are going to start rant about 720p recording in dalvik thread like he did?
Click to expand...
Click to collapse
Nah... I was just messing with you
I'm a noob really and don't understand much of this "data2sd scripts" and all that malarky. From my personal experience I was using a class 4 8gb with the dalvik on the card and found no issues with it. No lag's or pauses or anything. I've since moved to a class 10 16gb and decided to keep my dalvik on the nand because I don't need the extra space for 100's of apps like some people do - my needs for apps are simple
IF I did have a class 2 I'd be a bit worried about putting the dalvik onto it, but like you said, it depends on the random read/write speeds the card can handle.
ps: you should have had that answer the other day with island3r

zedmarcus said:
ps: you should have had that answer the other day with island3r
Click to expand...
Click to collapse
As I said I couldn't find it last night. I have no doubt he will see it here too. This puts a nice finishing touch to who was right and who was wrong so I have no need to reignite that discussion again

Anyone using Adoptable Storage? All my old cards are too slow...

My cards say class 10 and 50 MB/sec. Android says they are too slow.
How fast of a one do I need?
I don't want to buy a 128 card just to find out I need root to tweak the buffer or that it doesn't work that well.
I posted a screenshot. Adoptable is the same as storage, sdcard, 3dots, format as internal

From my understanding there aren't any cards at the moment quick enough to serve the role efficiently. Just use it as an external storage until faster cards become available.

I was about to make a post concerning the best Micro SD cards do Moto Z Play, thanks for bringing that up!
I have a 128gb Samsung EVO micro sd, class 10, but it's 48mb/s and I got the same message you did, saying the card isn't fast enough and that the overall apps and system speeds could be slower.
I thought class 10 micro sd's were among the fastest and the Moto Z Play wouldn't have any trouble using it as an extension of it's internal storage, but as a matter of fact, there are indeed faster micro sds. After researching a little bit, I found Samsung EVOs with 80mb/s transfer speeds (the 48mb/s are colored orange, as the 80mb/s are little green ones):
I still haven't bought one, but I browsed through some forums and videos and people with the same problem said 80mb/s seems to do the trick and they didn't get any message complaining about the micro sd speed.
f you want even faster micro sds, try the Sandisk Extreme, with speeds up to 90mb/s:
I have to get a faster micro SD anyway, as soon as i do i'll post here my experience with it.
Hope this helps,
Cheers!

While running the adopted 50 MB card AFT fails on most copy operations.
I am afraid ? that 2 times faster may not be enough for the already challenged ATF, buggy as it is already.

aviwdoowks said:
My cards say class 10 and 50 MB/sec. Android says they are too slow.
How fast of a one do I need?
I don't want to buy a 128 card just to find out I need root to tweak the buffer or that it doesn't work that well.
I posted a screenshot. Adoptable is the same as storage, sdcard, 3dots, format as internal
Click to expand...
Click to collapse
How can you live with all those notifications? My OCD prevents me from seeing so many icons in the notification bar

Jorgeprdz said:
How can you live with all those notifications? My OCD prevents me from seeing so many icons in the notification bar
Click to expand...
Click to collapse
Just 12 not including the statusbar pro, which I cannot live without.
Better?

Using this card with no issues. Formatted as internal storage. SanDisk Extreme 128GB microSDXC UHS-I Card with Adapter (SDSQXVF-128G-GN6MA). Got it at Amazon for 60 bucks. It is quite speedy as far as I can tell.

geomun said:
Using this card with no issues. Formatted as internal storage. SanDisk Extreme 128GB microSDXC UHS-I Card with Adapter (SDSQXVF-128G-GN6MA). Got it at Amazon for 60 bucks. It is quite speedy as far as I can tell.
Click to expand...
Click to collapse
Thanks
Do you play large music files (flac or dsf) ?
I do and getting them on such a card is via my Mac using Android File Transfer or from a SATA drive using OTG. On KK AFT did not work on large transfers. It has not been updated in many years. The OTG / drive method should be reliable but not with my 50 mb, slow card.
To boot, on the negative side of using adopted cards, you cannot pull the card in the case of a data wipe.
I will be abandoning this method.
Thanks to all for sharing!

aviwdoowks said:
Thanks
Do you play large music files (flac or dsf) ?
I do and getting them on such a card is via my Mac using Android File Transfer or from a SATA drive using OTG. On KK AFT did not work on large transfers. It has not been updated in many years. The OTG / drive method should be reliable but not with my 50 mb, slow card.
To boot, on the negative side of using adopted cards, you cannot pull the card in the case of a data wipe.
I will be abandoning this method.
Thanks to all for sharing!
Click to expand...
Click to collapse
In my use case, adaptable storage doesn't make much sense on devices with 32gb or more of internal storage. Unless you really need that much space for app installs, the limitations outweigh the benefits. My typical app load is around 8 to 10gb, so I have somewhere around another 10 available on the MZP, as long as I pull all my media into an external card. This way I know all my apps are using fast internal storage, and I don't have to wonder if a widget is available or not. And I can pull the card and use it in a PC or other device.
Now my Moto E 2 (with 8gb onboard) is a different story. But I use a hybrid card in that - 20gb as adopted and the other 40 as external. May consider this as an option when I get around to getting a card for the MZP

I took a 32gb card and combined it. It warned me too. After reading up on the function, Android evaluates what to put where. Having the card separate made it less useful only good for photos and video really. This way app data can be buffered there. Things like cloud services buffer files internally. Netflix now uses SD but that was an issue too.

Bought a new micro SD for the Moto Z Play and it works perfectly with no warnings about it's speed being slow!
It's a Samsung PRO 64 GB microSDXC Card, with 90 MB/s reading speed and 80 MB/s writing speed.
As you insert the card and format it to be part of the phone's internal storage, the system doesn't complain about the card being too slow or that it'll affect the overall app and system speed.
It's perfectly reliable for installing apps outside the device storage and keep the desired speed and all that good stuff.
Cheers! =)

arides said:
It's perfectly reliable for installing apps outside the device storage and keep the desired speed and all that good stuff.
Click to expand...
Click to collapse
It's a microSD. For these kind of cards it's quite usual that there is some percentage that fail after some time. Some cards only last for months, other years. It seems to be independent of manufacturer.
My personal advice: Whatever you store on a micro SD card, have a backup. I'd rather not use it for internal storage if it's not necessary to do so. It's slower than internal memory anyway. This is a personal opinion, you'll have or see different opinions for sure.

tag68 said:
It's a microSD. For these kind of cards it's quite usual that there is some percentage that fail after some time. Some cards only last for months, other years. It seems to be independent of manufacturer.
My personal advice: Whatever you store on a micro SD card, have a backup. I'd rather not use it for internal storage if it's not necessary to do so. It's slower than internal memory anyway. This is a personal opinion, you'll have or see different opinions for sure.
Click to expand...
Click to collapse
I agree but for me having a Mac I never want to use ATF it is buggy.
So I am left to getting large music files from an external drive over OTG.
It is so much more reliable to drop the file right to the SD and move the card to the phone.
If the adopted card fails , you need a data wipe or an update screws it up, you have a bad phone day!

aviwdoowks said:
I agree but for me having a Mac I never want to use ATF it is buggy.
Click to expand...
Click to collapse
Me too!
I'm allowing the access via Windows filesharing (still OSX 10.6.8), and then access some drive on the computer using LAN plugin of Total Commander for Android. Works like a charm! It is a bit slower, but very convenient not having the need to put card or, put card in etc.

tag68 said:
It's a microSD. For these kind of cards it's quite usual that there is some percentage that fail after some time. Some cards only last for months, other years. It seems to be independent of manufacturer.
My personal advice: Whatever you store on a micro SD card, have a backup. I'd rather not use it for internal storage if it's not necessary to do so. It's slower than internal memory anyway. This is a personal opinion, you'll have or see different opinions for sure.
Click to expand...
Click to collapse
tag68 said:
Me too!
I'm allowing the access via Windows filesharing (still OSX 10.6.8), and then access some drive on the computer using LAN plugin of Total Commander for Android. Works like a charm! It is a bit slower, but very convenient not having the need to put card or, put card in etc.
Click to expand...
Click to collapse
Is that only on snow?
I do have a snow partition for older programs.
So do I need to buy FC and the plugin?
Tell me more please, cause I hate ATF soooo much. Why does Android drop it's ball like this?

aviwdoowks said:
Is that only on snow?
Click to expand...
Click to collapse
I'm quite sure that file sharing via smb: is available on nearly all versions of Windows and OSX.
You may start Windows file sharing in network settings of OSX. Then you can give access to some drive in Finder.
If you google a bit, you will find help I guess.
aviwdoowks said:
So do I need to buy FC and the plugin?
Click to expand...
Click to collapse
Buy? Total Commander is free of cost, including all necessary plugins. For Windows file sharing (smb) you need the TC LAN plugin.
Edit: By "a bit slower" I meant because it usually is being used via WLAN in your intranet

Just wanted to post back here - finally got around to picking up an sd card for the MZP. Went with Samsung evo 128gb, $40 on Amazon. Since it's got plenty of space, I decided to go the same route that I did with the moto e, and do hybrid storage. Formatted 25% adopted and 75% external. Gives me an additional 30gb internal space and 90gb external storage.
Device sees the storage space fine. A couple apps I've messed with so far (Netflix and Google play music) can save to external fine, but don't recognize the additional available space in "internal", or at last don't report it as available.
I don't plan to move any apps that I use frequently or anything that I use widgets from to adopted, as the advertised max read speed is only 20mb/s. Haven't actually tested yet. But I did move a couple low use apps over. Reported storage space on both internal and adopted updated correctly (an issue I've had in the past).
So far, so good.