Very slow write speed on SSD S3520

[DRobi14]

I have experienced horribly slow write performance on both my S3520 240GB drives on Windows 7, and would like some guidance.

The details:

I have 4 Intel SSDs : 2 x 530 Series (SSDSC2BW120A4 and SSDSC2BW240A4), and 2 x S3520 240GB (SSDSC2BB240G7). I have the same very disparate performance with both pairs. In addition, I have 3rd S3520 in the field with the same problem.

The pair I will highlight is as follows:

530 Series 120GB

F/W version : DC32

S/N: PHD A41 660 0Z8 120 7GN

DC S3520 240GB

F/W version : N2011021

S/N: BTD V72 750 FRY 240 AGN

The problem: I have a proprietary OS running on a Pentium server box, which has its own driver to talk to these SSDs in IDE mode. The 530 performs very well, in line with benchmark data I can find on the Web. The S3520 performs well also, except In certain cases, where its average sector write time is 26x (yes, 26) that of the 530. We have managed to produce a specific test case where we write 15,634 single sectors of a 13MB file, with specific content in each sector, and the same non-consecutive order of disk addresses being written. The average write time for sector writes to the 520 is 0.06ms, and the average write time for the S3520 is 1.56ms.

At first we thought there must be some compatibility problem between our disk driver and this specific drive.

But I have constructed a Windows program which writes these same sectors to a second pair of drives, in the same order, on Windows 7 (using FILE_FLAG_NO_BUFFERING).

The result is the same: < 1 sec to write the 15,634 sectors on the 530, and > 20 sec on the S3520.

I can only conclude that the S3520 has some severe firmware problem which makes it sensitive to the content (and/or the order) of certain data being written.

Does anyone have any experience with similar problems here?

[DRobi14]

Your answer was a trifle ambiguous. You did say you tried an an S3520 in Windows 7 and saw normal write speeds. But you did not specify whether or not you tested it with the special test case which I supplied to you.

The reason I ask is this : I have tested my S3520 under Windows 7 with 5 different SSD benchmark tools and all of them say the drive performs with normal (excellent) write speeds. Only MY test case shows the problem - and bear in mind my test case shows normal write speeds on two other different SSDs on the same PC.

So there is definitely a problem with the drive.

Did you run my particular test case, or some other benchmark?

If you tried my test case, I suggest you have me ship my drive to you for testing.

thanks

Dave Robinson

[idata]

Hello DLRobinson,

Please check your private messages.Best regards,Eugenio F.

[DRobi14]

Eugenio,

Regarding this case (# 03122905), I received the below e-mail from you on Dec 11th 2017.

I see the error that the support people got when they attempted to run my test case.

My apologies - I failed to test the package in a directory that contained nothing except my test tools, and so missed the fact that the test program requires a DLL. I have attached the missing DLL. Please ask the support engineers to re-run the test case with the DLL. thank you Dave Robinson

Hello David, Thanks for your patience. I have received updates from our highest tier of support regarding this case. They weren't able to replicate the test you indicated. It returned an error saying "nosnetnt.dll" file is missing. Regular benchmark tests on the Intel® SSD DC S3520 Series (using latest firmware N2010121) showed no problems on Windows* 7 Professional 64-bit. As mentioned before, there are no other reports of this problem, nor were we able to find any other issues. Are you using a standard Windows 7* build? Also, would it be possible to send the failing setup to them? That would be ideal for clean replication and triage. Best regards, Eugenio F.Intel Customer Support

[idata]

Hello DLRobinson,

We have news regarding your request.Our higher level technicians were able to reproduce the test just as you indicated. and the results are expected behavior.Please bear in mind that https://www.intel.com/content/www/us/en/products/memory-storage/solid-state-drives/data-center-ssds.... Data Center drives should not be compared with https://www.intel.com/content/www/us/en/products/memory-storage/solid-state-drives/consumer-ssds.htm... Consumer SSD when talking about performance as these products are architect-ed differently with different capabilities and expected usages.The performance shows as defined in the https://ark.intel.com/products/93012/Intel-SSD-DC-S3520-Series-240GB-2_5in-SATA-6Gbs-3D1-MLC Specifications for Intel® SSD DC S3520 with CrystalDiskMark*; if different tools are used to measure performance (than the ones we specify, usually CrystalDiskMark* and IOMeter*), it might be expected to get different results.Best regards,Eugenio F.

[DRobi14]

Eugenio,

Sorry for the delay in getting back to you.

I have received the e-mail/post you sent on Dec 19th 2017, reproduced below.

I do not understand what you said about the high level technicians reproducing the test I gave you, and that "the results are expected behavior".

What you say does not really answer the most important question, which is this...

When they ran my test case, what was the elapsed time for the test? Was it close to the 20 seconds I experienced on the DC S3520?

If so, then the device failing to meet its specifications, just as it does for me. The specs, located at the link you sent me below, calls for 16,000 IOPS. At that rate, my test case of 15,634 sectors should run in less than one second instead of the > 20 sec which I see.

regards

Dave Robinson

========= Reproduced post =========

Hello DLRobinson,

We have news regarding your request.

Our higher level technicians were able to reproduce the test just as you indicated. and the results are expected behavior.

Please bear in mind that https://www.intel.com/content/www/us/en/products/memory-storage/solid-state-drives/data-center-ssds.... Data Center drives should not be compared with https://www.intel.com/content/www/us/en/products/memory-storage/solid-state-drives/consumer-ssds.htm... Consumer SSD when talking about performance as these products are architect-ed differently with different capabilities and expected usages.

The performance shows as defined in the https://ark.intel.com/products/93012/Intel-SSD-DC-S3520-Series-240GB-2_5in-SATA-6Gbs-3D1-MLC Specifications for Intel® SSD DC S3520 with CrystalDiskMark*; if different tools are used to measure performance (than the ones we specify, usually CrystalDiskMark* and IOMeter*), it might be expected to get different results.

Best regards,

Eugenio F.