topic Re: High latency for disk activity while writing file intel 80gb G1 in Archive

High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 02:38:32 GMT

I was writing a large file to my ssd and my system was basically crippled because the response time for programs went from the usual <=3ms to a peak of 817ms. I got this info from the disk activity tab under performance monitor. I've also noticed that when the drive stutters, it's because the latency increases to ~500ms. Is there a fix for this because buying another ssd with say a SF controller? I'm using a lattitude e6410 with the latest intel ahci drivers installed.

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 05:00:59 GMT

1) How long has the drive been in use?

2) How much free space did you have left on the SSD?

3) How big was the file?

It sounds like the SSD is out of clean blocks. Since there are no more clean blocks, the SSD has to read-modify-write and this leads to the classic symptom of high latency. This issue was resolved with newer SSD controllers with the implementation of a function called TRIM. Pretty much all controllers in the last 2 years support TRIM. Unfortunately, your SSD does not support TRIM or the Intel SSD Optimizer.

The only solution to resolve this problem for a few months is:

1) Take an image of current disk

2) Do a full reformat of the SSD

3) Apply image.

Here is the explaination of the issue in detail: http://www.anandtech.com/show/2738/8 http://www.anandtech.com/show/2738/8

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 05:41:08 GMT

1) about 2 months since the last format

2) 23GB

3) 14GB

shouldn't garbage collect take care the drive though? it's had 23GB free for a few weeks.

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 05:45:18 GMT

bah, it logged me out. ^ post is mine. the drive stuttered after my fresh format anyway. performed a full one using w7 on another comp

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 06:52:07 GMT

Guest wrote:

1) about 2 months since the last format

2) 23GB

3) 14GB

shouldn't garbage collect take care the drive though? it's had 23GB free for a few weeks.

What kind of format did you apply? A quick one?

Definitely sounds like a not enough clean blocks issue.

Intel SSDs do not implement garbage collection. If you have 23GB of dirty blocks, you will continue to have 23GB of dirty blocks.

You could attempt a "Tony TRIM": http://www.ocztechnologyforum.com/forum/showthread.php?64753-A-simple-guide-for-speeding-up-EOL-OCZ-SSD-s http://www.ocztechnologyforum.com/forum/showthread.php?64753-A-simple-guide-for-speeding-up-EOL-OCZ-SSD-s.

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 10:50:00 GMT

I would strongly recommend not doing that. I haven't tried it myself but users on other forums have said that whilst it works to some extent on OCZ drives it has the opposite effect on Intel drives.

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 10:54:59 GMT

Could you run an AS SSD benchmark and post the results?

http://www.alex-is.de/PHP/fusion/downloads.php?cat_id=4 http://www.alex-is.de/PHP/fusion/downloads.php?cat_id=4

Do you have write caching enabled?

Also try a secure erase:

http://www.pcper.com/article.php?aid=669&type=expert&pid=6 http://www.pcper.com/article.php?aid=669&type=expert&pid=6

It's sad that Intel chose not to provide TRIM functionality for the G1 drives.

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 11:20:42 GMT

write cache is enabled. i ran the optimizer thing in the ssd toolbox. an error popped up for the read access time

access times went up to 2.2s for the 4k-64thrd part

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 11:33:56 GMT

Boy that sucks. I'd run a secure erase to see if that clears it up. If that fails to improve things something other than the SSD may be at play.

Do you write heavily to the drive all the time?

EDIT: I see you are using MSACHI drivers. (Standard Win 7 default) If a secure erase resolves the problem I'd switch over to the latest Intel RST drivers. (Assuming you have Intel chipsets.)

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 11:55:23 GMT

A secure erase will work.

A G1 should eventually recover but when results are this low, secure erase is the only sensible option.

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 17:13:06 GMT

redux wrote:

I would strongly recommend not doing that. I haven't tried it myself but users on other forums have said that whilst it works to some extent on OCZ drives it has the opposite effect on Intel drives.

It was a matter of last resort other than zeroing the drive out. It already is pretty bad.

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 18:37:54 GMT

Use Ccleaner to wipe/erase the drive free space.

Re: High latency for disk activity while writing file intel 80gb G1

mmokk — Thu, 30 Dec 2010 19:12:06 GMT

the secure erase will restore performance*, guaranteed. anything else is 'maybe it will work, maybe not'.

given the choice between a 100% probability of positive outcome, and 50/50, this should be a no-brainer.

do check your firmware version first though, and update it if it's not the latest (8820)

* be aware that many laptops castrate sata performance. it's possible you will never see your g1 perform as well in your laptop as it would in a desktop. the secure erase should still reduce the high latency, though.

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 19:41:48 GMT

ccleaner will, it's not maybe it will work.

Re: High latency for disk activity while writing file intel 80gb G1

idata — Thu, 30 Dec 2010 20:19:05 GMT

when i hover over the msahci thing in the probram, it shows the intel chipset ahci driver, but hwen i check the drive under manage computer computer, it says it's the ms controller. seems kinda retarded that the only way to restore performance for a 2 month old drive is to erase it and copy the drive image over... here's atto btw. doens't seem like that as ssd thing shows the whole story.