Nexus 7 I/O speed issue

[hbkmog]

http://androidandme.com/2013/06/opi...from-the-best-to-worst-tablet-ive-ever-owned/

After reading the article, I'm glad I'm not the only one who's experiencing this issue. I've noticed my Nexus 7 slows down and becomes less responsive during heavy writing task(downloading stuff at high speed, stuttering browser, etc).

Before anybody jumping in and saying they don't have the issue, the point is it does happen and it happens to other devices as well. Same issue can be said for Galaxy Nexus, Asus Transformer Infinite Transformer Prime. A good way to test this is to see how your tablet performs when you download something over 1MB/s or 2MB/s.

The reasons some people don't see this are:

1. It's hard to tell in short term. Usually the memory i/o speed degrading starts to show after 6 months to 1 year or longer depending on the quality of the flash memory they use.

2. Interfering factors. Many people think the lag is caused by ROM or kernel. It could be true in some cases.

3. Inconsistent quality control during manufacture. I'd assume that out of some bad batches, there will be also some good units. Also not every device use the exact same flash memory chips.

4. Personal usage difference. Flash memory's life span depends on the limited number of writing/reading. So the degrading rate also depends on each individual. Some people are heavy users who constantly perform copying/reading/removing actions on the device while some others may only use it for internet access which results in less taxing work.

Actually the i/o speed issue is one main reason I'm looking forward to next generation Nexus 7. Just hope ASUS can use better quality flash memory next time.

EDIT: more elaborate point.

Sent from my Nexus 7 using xda app-developers app

 

[adamhlj]

http://androidandme.com/2013/06/opi...from-the-best-to-worst-tablet-ive-ever-owned/

After reading the article, I'm glad I'm not the only one who's experiencing this issue. Before anybody jumping in and saying they don't have the issue, the point is it does happen. Same issue can be said for Galaxy Nexus and Asus Transformer Prime. Actually this is one main reason I'm looking forward to next generation Nexus 7. Just hope ASUS can use better quality flash memory next time.



Sent from my Nexus 7 using xda app-developers app

I don't know, if Asus doesn't get it right on 2 devices, all of which I have owned, I can't imagine that they will get it right on the next 2 devices. I was so tired of my laggy infinity that I just sold it on ebay. I was so tired of my laggy nexus 7 that I did a factory reset. But then again, these were essentially first generation products. Hopefully the second gen will be better (seems to contradict what I just said, haha.) I am probably going to wait for a little while before I get the next nexus, anyway. I have an expensive habit of getting the latest on launch, most of the time regretting my decisions.

 

[armada786]

I haven't seen any of the lag these sites and users complain about. Maybe its because I was more used to my Iconia A500 dragging its feet at the two year mark but I can't see how this is "laggy" or "unresponsive" at all. I think this is the result of seeing the device as "old" rather than "new" so you notice one thing and look for 100 others you never noticed. In the end though it could be worse. You could've paid a pretty penny for it to turn to crap All I can say is that I have not noticed these problems and that if they remain after a wipe and reversion to an older, version then they must have always been there.

 

[kieso]

Its flash storage over all devices. I've seen the same lag on my wifes ipad and iphone.

 

[hbkmog]

I haven't seen any of the lag these sites and users complain about. Maybe its because I was more used to my Iconia A500 dragging its feet at the two year mark but I can't see how this is "laggy" or "unresponsive" at all. I think this is the result of seeing the device as "old" rather than "new" so you notice one thing and look for 100 others you never noticed. In the end though it could be worse. You could've paid a pretty penny for it to turn to crap All I can say is that I have not noticed these problems and that if they remain after a wipe and reversion to an older, version then they must have always been there.

Well, the thing is the performance drop is very distinct and easy to see. When the device comes to a stall during some background writing/reading, then it's problem.

The reason some people don't see this is:

1. It's hard to tell in short term. Usually the memory i/o speed degrading starts to show after 6 months to 1 year or longer.

2. Interfering factors. Many people think the lag is caused by ROM or kernel. It could be true.

3. Inconsistent quality control. I'd assume that out of some bad batch, there will be also some good units. Also not every device use the exact same memory chips.

4. Personal usage difference. Flash memory's life span depends on the limited number of writing/reading. So the degrading rate also depends on each individual. Some people are heavy users who constantly perform copying/reading/removing actions on the device while some others may only use it for internet access which results in less taxing work.

 

[bftb0]

http://androidandme.com/2013/06/opi...from-the-best-to-worst-tablet-ive-ever-owned/

After reading the article, I'm glad I'm not the only one who's experiencing this issue. I've noticed my Nexus 7 slows down and becomes less responsive during heavy writing task(downloading stuff at high speed, stuttering browser, etc).

Every computer I have ever used - that's over a 30-year period - could have its' UI brought to it's knees with heavy I/O. It's not a surprise, really: mass storage is typically the slowest bandwidth device (ignoring things like uarts or keyboards) in the system.

The problem can be pushed into a corner - for instance using massively more RAM than is needed by the memory footprint of the kernel and apps, so that there is plenty of fast file cache available, but even in that case, a source of sustained high-speed I/O will eventually exhaust the write cache, and slow writes will start occurring and queuing up against all other I/O activity.

But that kind of thing doesn't happen in a $200 tablet. RAM ain't cheap, nor does it come for free in terms of power consumption (and thus battery size needed for a given "on battery" time).

On top of that, you have all the problems of write amplification that occurs with flash memory that performs block erasures and wear-leveling.

IMO, if you think this is something that only occurs on certain OS releases, or certain hardware, you are probably going to be disappointed with every device you ever buy. That will be the case until a non-volatile storage media exists with sustained read/write bandwidth that exceeds that of the system memory bus, and also is not affected by the number of independent transactions per GB of I/O.

BTW, the fact that someone on the internet complains about a problem with symptoms similar to those you experience does not imply that the same root cause is involved, nor does it say anything about the frequency of occurrence of those symptoms amongst the general population. I suppose that some small percentage of the world's population is tired all the time; but that doesn't mean they all have Lyme disease, nor that everybody has it.

cheers

 

[zwolf4444]

Gruber linked to it. Joy. Prepare for this article to be linked to by every iOS fanboy from now until the end of time.

My theory is that its mostly prevalent on the 8 GB models that were only sold for a short period of time, and thats why only a few people, mostly early adopters, have seen this.

 

[Keion]

I torrent ... "things" ... at over 1.5 MB/sec.
Don't see a dip in speed at all. Try changing your IO schedulers, people.

 

[T-Keith]

Mine gets slow when I have less than 3gb of storage open.. Above that, it is fast. It's not a permanent problem. Try freeing up space before damning the Nexus 7.

Sent from my Galaxy Nexus using xda premium

 

[BrianDigital]

Also as soon as some one points out an issue, people will come in and tell them they are wrong.

There's def an issue with the n7, sometimes is it is slow as molasses and other times butter smooth. Where as my n4 is always butter smooth

 

[lolcopter]

Mine gets slow when I have less than 3gb of storage open..

ya think?!?!

 

[bftb0]

Also as soon as some one points out an issue, people will come in and tell them they are wrong.

There's def an issue with the n7, sometimes is it is slow as molasses and other times butter smooth. Where as my n4 is always butter smooth

The N4 has twice as much RAM as the N7. See my comment about file write caching above. It is quite reasonable to expect the N4 to perform better under equivalent load as there will be substantially larger free memory for write caching (everything else being equal). Simply put the N7 will hit the I/O queue wait wall first.

A statement from one or two users that "my tablet doesn't do that, what are you talking about" is just as relevant information as one or two users claiming "my tablet is always slow".

Neither report is a denial of the experiences of others; but both taken together are a demonstration that the trouble described is not universally experienced.

And since neither set of onesie-twosie reports represent a statistically significant sample, neither of them are capable of saying anything meaningful about how widespread the problem is in the general user population.

cheers

 

[Rirere]

The N4 has twice as much RAM as the N7. See my comment about file write caching above. It is quite reasonable to expect the N4 to perform better under equivalent load as there will be substantially larger free memory for write caching (everything else being equal). Simply put the N7 will hit the I/O queue wait wall first.

A statement from one or two users that "my tablet doesn't do that, what are you talking about" is just as relevant information as one or two users claiming "my tablet is always slow".

Neither report is a denial of the experiences of others; but both taken together are a demonstration that the trouble described is not universally experienced.

And since neither set of onesie-twosie reports represent a statistically significant sample, neither of them are capable of saying anything meaningful about how widespread the problem is in the general user population.

cheers

I'd also be surprised if most Nexus 4s have had the same amount of wear on them as the Nexus 7s. Just saying.

Your I/O scheduler definitely helps, but unfortunately software fixes can only play catch-up for so long. It's one of the things I really do dislike about flash memory-- yes, I know that spinning disk media also has wear, but I've had some drives running for...practically forever, really. I just don't feel comfortable knowing that SSDs and flash will eventually cop out because of how they're designed (but a lot of that, I'll plainly admit is a psychological thing and has little to do with the tech's actual reliability).

 

[BrianDigital]

The N4 has twice as much RAM as the N7. See my comment about file write caching above. It is quite reasonable to expect the N4 to perform better under equivalent load as there will be substantially larger free memory for write caching (everything else being equal). Simply put the N7 will hit the I/O queue wait wall first.

A statement from one or two users that "my tablet doesn't do that, what are you talking about" is just as relevant information as one or two users claiming "my tablet is always slow".

Neither report is a denial of the experiences of others; but both taken together are a demonstration that the trouble described is not universally experienced.

And since neither set of onesie-twosie reports represent a statistically significant sample, neither of them are capable of saying anything meaningful about how widespread the problem is in the general user population.

cheers

Your right when I wake my n7 from sleep with no apps updating or anything running, and it moves at a ants pace. I am wrong its me I guess...right. Every user should have to unlock root and flash a kernel to change how it runs.

I read the comment you made before, its the same copy pasta stuff from when the nexus 7 didn't have issues having the storage full, back early on. This what makes xda so great, people have a issue and someone chimes in tells them they are wrong, or ten posts of "420 root it, and flash mer devs kernel"

But your right my tablet should mostly be lagging because running the launcher and maybe an app slows everything down because its designed to run an app and that's it.

Cheers

 

[armada786]

EDIT: bftb0 summed up what I wanted to say far better

 

[bftb0]

Your right when I wake my n7 from sleep with no apps updating or anything running, and it moves at a ants pace. I am wrong its me I guess...right. Every user should have to unlock root and flash a kernel to change how it runs.

Nobody has denied anybody's experience. If you say that stuff happens, I believe you.

I read the comment you made before, its the same copy pasta stuff from when the nexus 7 didn't have issues having the storage full, back early on. This what makes xda so great, people have a issue and someone chimes in tells them they are wrong, or ten posts of "420 root it, and flash mer devs kernel"

off topic = irrelevant. But nice segue.

But your right my tablet should mostly be lagging because running the launcher and maybe an app slows everything down because its designed to run an app and that's it.

If that happens on a stock device with no apps that's been rebooted within the past few days, and there are no other pathologies involved (e.g. nearly-full or corrupted file systems), then *probably* there is a hardware problem involved.

Look, I get it. Plenty of folks just want to use their device, not worry about details, and have it work as if it were mint. And they want it to behave that way even after customization (adding random apps). But practical experience with a wide variety of computing devices reveals that performance problems always hinge on details - sometimes incredibly tiny and obscure details. Those "details" can be any number of things - "soft" (correctable) hardware defects, bugs in the OS software, user software that is installed, all sorts of stuff. And even for technically sophisticated users isolating the root cause can be difficult. Until some detective work has occurred, there is no justification to place the blame on any specific component.

BTW, I know how frustrating it can be. My old Android phone (rooted, OC'ed & CM 7 ROM) currently can not be operated with both the messaging app and launcher app locked in memory (It only has 190 MB of RAM!). So I get to choose between losing text messages or waiting 15 seconds !!! for the launcher app to repaint the first home screen after leaving a resource-hungry foreground app such as Maps or the Browser. If I try and set up the Android LMK to do aggressive memory reclaim, the device will occasionally enter a "thrash of death" where the LMK is killing off threads as fast as they are generated - and the whole device will go frozen for minutes at a time. So, yeah, I get the frustration.

That of course is indeed "my fault". I could go back to a factory stock ROM (Eclair w/ HTC Sense - ugh). But I don't want to. I want certain features, and I want certain apps, too. You might claim that's not comparable to a user having a stock ROM device with a whole bunch of market apps installed; but until those apps can be cleared of suspicion, blame cannot conclusively be laid anywhere.

It is what it is. Computers that do not exhibit load dependent performance problems do not exist. That doesn't make things anybody's "fault" - but it is highly unlikely that Google (or Apple, whomever) is going to send someone over to your house to figure out what goes on with your tablet.

So, moaning about a problem on the internet might make someone feel better for a few minutes, but at the end of those few minutes, the problem(s) will still be there.

And BTW I completely get it that if I were to be having a performance issue on my tablet, and I wanted to clear my 72 market apps from suspicion, it would take me as many as log2(72) ~= 7 binary bisection trials (remove half of apps each trial) to finger a suspect or clear them all from suspicion). Pain in the rear to be sure; but it wouldn't be any less work on a different device - Apple, Asus, HTC, Moto, Samsung, whatever. And if it were an intermittent problem? It might take a huge effort to isolate the cause. Way longer amounts of time than simply ignoring a second or two of hesitation in the UI.

But the OP created this thread in the General section, not the Help / Q & A section; was he even interested in getting help?


.

 

[tvdang7]

I too feel this way since 4.2 update. I'm stock unrooted with 7gb free of storage.

Sent from my Nexus 7 using xda app-developers app

 

[Phenryth]

Try rooting your device, install lagfix.
From the comments in the article linked by Op, should help.
I did not try myself since I'm not having these issues.

Sent from my Nexus 7 using xda premium

 

[GldRush98]

Try rooting your device, install lagfix.
From the comments in the article linked by Op, should help.
I did not try myself since I'm not having these issues.

Sent from my Nexus 7 using xda premium

Werd. Lagfix made my 7 feel like new again. I scheduled it to run once a week and haven't had any problems since then.

 

[hbkmog]

Try rooting your device, install lagfix.
From the comments in the article linked by Op, should help.
I did not try myself since I'm not having these issues.

Sent from my Nexus 7 using xda premium

Lagfix does fasttrim command but many kernals nowadays do that already so the effect could be placebo unless you are on the kernel that doesn't fasttrim well.

Sent from my Nexus 4 using xda app-developers app