Very poor performance of SSD on a SAS controller

[tomasz86]

I wonder what caues such a poor performance of SSD on a PCI-E LSI Logic 3042E SAS controller:

1.Samsung 470 @ LSI Logic 3042E

2. Samsung 830 @ LSI Logic 3042E

On the other hand below you can see how the drive "should" work:

3. Samsung 470 @ AMD A55 SATA2 controller

And lastly, this is a RAID0 of 2x Fujitsu MAX3036RC (37GB 15000 rpm SAS drive) on the same LSI controller...

4. 2x Fujitsu MAX3036RC @ LSI Logic

I know that the controller can limit the sequentional transfer rates but has anyone got any idea why the 4K values are so bad? :/

I have also noticed that copying files and other operations are not smooth when the SSD is connected to the LSI Logic controller while there are no problems when connected to the AMD A55 one.

Of course everything happens on the same mainboard (ASRock A55 Pro3) and the LSI controller is connected to the second PCI-E (x4) slot.

Edit: Added spoilers.

Edited August 24, 2012 by tomasz86

[MHD]

I wonder what caues such a poor performance of SSD on a PCI-E SAS controller:

Probably you are testing your SSD with small files? Try doing it with large files to examine the real performance

[tomasz86]

Well, I ran exactly the same benchmark (CrystalDiskMark) using exactly the same drive (Samsung 470) on two different controllers. The difference in results is huge :/

Edited May 6, 2012 by tomasz86

[allen2]

Maybe you could tweak your lsi controller to get better performance but you won't get great speed with this very basic controller (even using a raid 0): You could try to enable or disable the disk read/write cache (some raid controller disable it and this one disable it usually), you could create a tweaked raid volume depending on the data stored (small files need usually a small strip size).

[tomasz86]

It's a late reply but I just want to say that you were right! Write cache is disabled by default when the drive is connected to this controller.

The 4K values are much better after enabling it. It's the same Samsung 470 64GB @ LSI Logic 3042E:

Thank you

Edit: Added spoiler.

Edited August 24, 2012 by tomasz86

[tomasz86]

I've connected Seagate Cheetah 15K.7 600 GB to the same controller:

Now I'm really curious why linear transfer speed of the SSD is so low (133 / 109 MB/s) when this HDD reaches almost 200 MB/s

[allen2]

People think that SSD are faster than hard drive in every domain and it is wrong:

- Using incompressible data or not will give you completly different result. So depending on your usage, ssd might not be the right choice.

- Raid controller were optimized for hard drive not for ssd.

- Raid controller disable garbage collection (trim) so even if your OS support it, it won't happen unless the drive is able to do it by itself.

- You also took one the fastest enterprise hard drive and you're comparing it to a main stream ssd.

[tomasz86]

The problem here seems to be actually different.

The controller recognises the SSD as an ATA133 disk and reduces its speed to ATA133. That's why its sequential read speed is always ~130 MB/s.

This isn't the newest controller and there are absolutely no options in its BIOS to manage the disks except for creating RAID0/1 arrays so probably nothing can be done in this particular situation. The controller itself is capable of higher speeds as can be seen in case of the Seagate Cheetah disk tested before.

Edited November 12, 2012 by tomasz86

[Tripredacus]

Well I looked at the specs of that card (on the website) and the latest OS it supports if Windows XP. Not even any Server 2003 support. It seems to me that the current firmware on that card probably doesn't know what an SSD is. Did you check to see if there was a firmware update is available for it?

[tomasz86]

Actually this controller uses exactly the same drivers as LSI 1064E and they are available up to Windows 7 / Windows Server 2008 R2:

http://www.lsi.com/products/storagecomponents/Pages/LSISAS1064E.aspx

There are no firmware updates listed there though. I'll try to look for them elsewhere. My model (3042E) was originally branded by HP but I can't find it on their website any more.

I'm not sure whether the firmware for 3041E is compatible.

Edit: I've just checked Hardware ID of the controller and it's:

VEN_1000&DEV_0056&SUBSYS_322B103C&REV_08

which is in fact exactly the same as 1064E:

http://www.driveridentifier.com/scan/driver_file_detail.php?inf_file_id=113718&md5=16c52c76c79f55197233a71017fc62eb&scanid=BF6AFF661B7348C59AB523ED6E074387&item_id=122202885&hardware_id=PCI\VEN_1000%26DEV_0056

Edited November 13, 2012 by tomasz86