MicroSD Wear Leveling? - General Accessories

Do microsd cards have wear leveling circuitry in them? they're so small and i can't find any documentation which talks about only the microsd cards.
I only found documentation where all the features of flash media was bundled together

This is an old post, but i wonder exactly the same.
Newbie16 said:
Do microsd cards have wear leveling circuitry in them? they're so small and i can't find any documentation which talks about only the microsd cards.
I only found documentation where all the features of flash media was bundled together
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I just found this info here:
http // answerpot. com/ showthread.php?251530-MicroSD+card+%2F+NAND+wear+leveling+algorithm
Hi,
On a prototype device which we plan to mass produce for customer deployment, we are facing failures for the microSD card, using authentic SanDisk microSD cards. We ran through a couple of permutations of card manufacturers are it is related to the file allocation table.
I am using ext3 on the microSD card partition to run android.
Although MicroSD cards have built in wear leveling, it seems that many of them rely on a file allocation table to balance wear, such as the ones used by FAT. ext3 is a journaling filesystem; as such, it lacks a file allocation table, and adds a journal, which is a very high data turnover disk area. It seems that the sd card wear leveling tends to be crude, and may not be smart enough to move the physical location of the journal, which means that it is likely to fail quickly.
So, is there a solution to this issue, when using MicroSD cards with android?
Does the Micron POP memory device have some sort of built-in hardware wear leveling algorithm? Or is it in software and is the algorithms in the linux kernel sufficient to take NAND wear leveling into account?
Best regards,
Elvis Dowson
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If this info is correct, apparently microsd indeed has wear laveling, but it won't work at all with ext3, or i guess any other filesytem without a file allocation table.
So, any of you using ext3 partitions will have a less lifespan memory card.

i wonder it also..

Is this still true in ext4?

0
this is the 4th time that recently bought authentic ( h2testw tested) 64 GB and 128 GB micro SD cards got corrupted.
I am totally bewildered and this has been the most frustrating ordeal for me. I am using these on my mobile running Nougat 7.0 . in all cases I use the microSD card formatted into two partitions ext4 for or app2SD (or link2sd depending on what you use) linked data & other exFAT partition which is my main data partition. I can broadly divide my card into three areas based on usages
mostly RO
here I store all my I useful personal data - movies family pictures and stuff. this area is mostly read only.
moderate RW
pictures and movies coming from my camera
High RW
this is the binded WhatsApp folder I did not use the word link because this is not a symbolic link in that sense -the target is a different file system folder.viz exFAT so it is a bind that connects a F2FS partition folder to exFAT and I use app2SD folder mount feature to get this done
now the problem -depending on my luck from 2 months to 8 months in using these cards there is data corruption.I will not be able to write in WhatsApp image directory- that is the symptom that got me looking into this. I ran a chkdsk. with /r /x options & finally error out giving me the message that it ran out of free blocks.
now now what are my options
<> if I recover as much data as possible and reformat the partition, would that it take care of of the problem and how to avoid this in the future
<>toss the card in the trash bin and buy another new card and think of a different partitioning strategy that will be prevent this
<>now coming to the most important question . what would prevent this situation from happening how about if
<<>> I change the partition type and use FAT32 or ext4 - would that changed the outcome anyway
<<>> I will create totally 4 ext4 partitions including 1 for app2SD and other three for mostly RO, moderate RW and hi RW . how would this pan out in context of wear leveling. A F A I K wear leveling is oblivious of existence of partitions and it would still move around blocks to balance out or will it respect partition boundaries this is for not SSD but micro SD card ?
<> I Wonder if there exists some kind of a virusware that deliberately eats away into file bytes and corrupts them - I use malwarebytes to scan but so far nothing has shown up.
<> is it possible at the level of firmware to disable wear leveling.

Related

many files on SDHC card slows the device down/eats RAM ?

hi, is it true that the device eats more RAM, and gets slower when a SD Card with many files is in use ?
if so, is it the number of programs (links in \windows\start menu\) , or documents, or just the number of files in the FAT32 system that causes it ?
is that true?
does not seem like it is, I tested by simply removing the SDHC , (not removing all shortcuts) - and there were no significant change.
Next time, I'll compare before/after copying in all links that points to SD.
slayerns said:
is that true?
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Generally speaking, not at all.
If you put apps there, they may take very slightly longer to start. But once they start, they all run out of ran.
If you have a lot of data files, say music, the music player you are using may be indexing the files in the background. That will slow it down until the files are indexed.
I use an 8Gb card and have never seen a slowdown.

Max 2GB storage access for app !

There you go!
http://wmpoweruser.com/?p=15451
Techticker.co.uk have published this summary of the recently held UK TechDays seminar held by Microsoft to introduce developers to their new mobile OS.
While the 9 minute video by and large cover information we have heard earlier, one issue of note is that apparently each application will only have access to 2 GB of storage on the device, irrespective of the actual size of storage.
Don't really see that as a problem; the main storage hogs are going to be music/videos/pictures, which are handled through accesible libraries without this 2GB limit. Maps for GPS apps could hit the limit, although I think I see the envisaged scenario being more on streamed data with caching.
Yeah I don't see what's the problem here. Just more BS drama from WMPoweruser to generate traffic.
Tito662 said:
Yeah I don't see what's the problem here. Just more BS drama from WMPoweruser to generate traffic.
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The problem is that it's just heuristic restrictions on the usage of the operating system.
Why would you limit the size of the space an application can use? Is the underlying OS FAT32 and Microsoft is worried that stupid app developers will store everything as one monolithic file and therefore break their app when the store reaches 2GB?
It doesn't make sense, and restrictions that don't make sense -- regardless of what they are -- are a problem.
Yea, this is pretty restrictive, but you guys make it sound like 512MBs. How many apps do you have installed on your device as of now?
Spike15 said:
The problem is that it's just heuristic restrictions on the usage of the operating system.
Why would you limit the size of the space an application can use? Is the underlying OS FAT32 and Microsoft is worried that stupid app developers will store everything as one monolithic file and therefore break their app when the store reaches 2GB?
It doesn't make sense, and restrictions that don't make sense -- regardless of what they are -- are a problem.
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No, it's Silverlight Isolated Storage for saving stuff 'on disk'. SIS stores have specificed, finite sizes. Who knows, it might be fat32, might be exfat.
Spike15 said:
The problem is that it's just heuristic restrictions on the usage of the operating system.
Why would you limit the size of the space an application can use? Is the underlying OS FAT32 and Microsoft is worried that stupid app developers will store everything as one monolithic file and therefore break their app when the store reaches 2GB?
It doesn't make sense, and restrictions that don't make sense -- regardless of what they are -- are a problem.
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This is limited by Silvelight...
but i don't think this is a big problem,this limitation can easy change by update
This isn't really accurate. They haven't fully decided on a max space. WP7 uses exFAT and isn't limited to a single file size. I believe this can be configured per app and developers will be able to request more than 2GB if their app needs it for whatever reason. 2GB is just the 'default' and isn't even enforced in the CTP. http://msdn.microsoft.com/en-us/library/ff402541(v=VS.92).aspx
My bigger problem with this isolated storage is that for no reason at all other than bad engineering it's incredibly slow. sviluppomobile.blogspot.com/2010/04/wp7-isolatedstorage-speed.html about 127x slower.
When I posted about this on the msdn forum, some MVP just basically told me to "use a webservice" and if i don't than this is not the platform for me.
I had issues with that when i was making some silverlight apps some time ago. But i figured them out. What microsoft is doing here with windows phone 7 is that they are using the phone to marry apps with their cloud counterparts. Apps like netflix ap mobile nytimes will use if at most 10 mb of local storage on the device. anyone that need more than 512 mb of local storage for their app, is doing something really wrong. in regards to speed of the local storage i have realised that each local storage created is essential a true isolated storage area. meaning its essentially a small partiton formatted in some format (might be fat) and all the process of reading from that and storing to it really gets some painful io problems. But it seems with windows phone 7 the unified storage engine seems to fix that. Essential from my views of the way my programs are working. when an app is launched. all other apps are essentialy frozen in their last state, so only essential apps and stacks are running. during this process the local storage is put into ram and the application access the program at close to the native speed of the ram. when a user hits the back button it essential takes the local storage and saves back to the slower storage medium and saves the state of the application..
hope this makes sense.
What do you plan on installing on your WP7? World of Warcraft?
Imho, you don't need more than 2 gigs per app, hell, even my Tomtom with all Europe installed on it fits on my 2 gigs microSD card.
Remember, it's a freaking phone!

[Q] Running Torrents on T2 Ultra Dual

Hi friends,
I have a Sony Xperia T2 Ultra Dual smart phone with me. I would like to know if I can download public domain materials using a bit torrent client on my phone? Is the phone built to sustain long periods of downloads (say 10-12 ) hours continuously. One of my friends is a nature researcher and uploads photos, videos and mp3 about nature as a torrent file, which I can download using torrent client - utorrent. The size amounts to around 4 GB per day and I would be downloading every day for the next 3-4 months. Can the phone sustain it without getting damaged? Also where should I save the files, in phone memory or SD card? Thank you.
harishkumar09 said:
Hi friends,
I have a Sony Xperia T2 Ultra Dual smart phone with me. I would like to know if I can download public domain materials using a bit torrent client on my phone? Is the phone built to sustain long periods of downloads (say 10-12 ) hours continuously. One of my friends is a nature researcher and uploads photos, videos and mp3 about nature as a torrent file, which I can download using torrent client - utorrent. The size amounts to around 4 GB per day and I would be downloading every day for the next 3-4 months. Can the phone sustain it without getting damaged? Also where should I save the files, in phone memory or SD card? Thank you.
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T2 ultra has only 8GB internal memory, you may not want to download files around 4GB on internal memory, I'm not sure whether the torrent client allows you to save files on SD card, if it allows, you may download files using torrents.....
and yes phone sustains it, they are so called "smartphones"
may be your battery will have hard time if you download them daily, device may heat up, but sony has inbuilt device temperature moderator...
Thanks Krishna!
krishna442 said:
T2 ultra has only 8GB internal memory, you may not want to download files around 4GB on internal memory, I'm not sure whether the torrent client allows you to save files on SD card, if it allows, you may download files using torrents.....
and yes phone sustains it, they are so called "smartphones"
may be your battery will have hard time if you download them daily, device may heat up, but sony has inbuilt device temperature moderator...
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Click to collapse
Thanks Krishna, very much. I was out of station, that is why I could not thank you earlier. By the way, my built in file commander says that the amount of memory is only 4 GB, whereas you are saying it is 8 GB!
harishkumar09 said:
Thanks Krishna, very much. I was out of station, that is why I could not thank you earlier. By the way, my built in file commander says that the amount of memory is only 4 GB, whereas you are saying it is 8 GB!
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Click to collapse
T2 ultra dual has internal memory of 8GB of which 4GB is available for users data storage & installation,
the other 4GB is used by device for OS installation & other stuff,
that's why, file commander or other file managers will show only 4GB of device memory available
You can add memory (SD)card, max capacity 32GB as officially denoted by sony,
for storage (& installation, only if you have root access) purposes..
you can move only apps on SD card without root access. no app data.
Also I have read somewhere on this forum that,
T2 ultra single & dual sim, device, can support larger capacity SD cards like 128GB, I have never tried it.
rrd84 said:
T2 ultra dual has internal memory of 8GB of which 4GB is available for users data storage & installation,
the other 4GB is used by device for OS installation & other stuff,
that's why, file commander or other file managers will show only 4GB of device memory available
You can add memory (SD)card, max capacity 32GB as officially denoted by sony,
for storage (& installation, only if you have root access) purposes..
you can move only apps on SD card without root access. no app data.
Also I have read somewhere on this forum that,
T2 ultra single & dual sim, device, can support larger capacity SD cards like 128GB, I have never tried it.
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Click to collapse
Thanks rrd84 for your kind clarification.

Adaptable storage

Ok, so Big Red left out YET ANOTHER nice MM feature. But guess what? We can put it back in! http://forum.xda-developers.com/showthread.php?t=3309709
I did this, and in page 6, there's also another link to partition your sd card to have both! The number used in the command line....'mixed xx' refers to the percent of public, not emulated storage. Just sharing what I found. Not a pro, but have dabbled some, and read A LOT before doing so. "Disclaimers" Sorry if in the wrong thread.
Damn sd card problem of virtual, automatic removal still throws a wrench in the system.

SD card prioritized..?

Hi, I have looked in the past for an answer but does our phone (att model) have the ability to use SD card as primary storage, especially for games? I hoping just overlooked something. Although some apps do merge internal & external for storage calculations, that's the best I get..
Seems pointless to even have a branch of this nice feature if I still have to uninstall stuff to make space..
Thanks in advance!

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