recommended strip size (6x SSD in RAID10)

[DFrea]

Hello,

what is recommended strip size for 6x Intel SSD DC S3510 Series 1,2TB SATA3 in RAID10 (on LSI2208 raid controller)?

And what would be recommended strip size for 2x SSD in RAID1?

Thank you...

[jbenavides]

Hello d3vl1n,

There are different things you have to consider in order to determine the best RAID stripe size for your system: Storage container, RAID controller, type of workload, etc.

From the SSD perspective, it is good to note that the Intel® SSD DC S3510 has a default Sector size of 512 Bytes, and Physical Sector Size of 4KB (4096 bytes). So, a Stripe size in multiples of 4,096 Bytes should work well. Also keep in mind that proper File System Alignment will also help performance and endurance.

Additionally, we advise you to check with LSI http://www.avagotech.com/support/ Support or the http://www.intel.com/support/oems.htm Computer Manufacturer Support, since they may have a recommended stripe size for their device depending on the RAID level.

Also, the best choice for the stripe size may depend on the type of workload, random data vs sequential and the typical file transfer size. In some cases, the software vendors may provide documentation on how to select the best RAID stripe size for their applications.

Common stripe sizes may be 16KB, 64 KB, 512KB, 1 MB, etc. Either one should work fine from the SSD side.

Here are some documents that you may use for reference:

http://www.intel.com/content/www/us/en/solid-state-drives/ssd-partition-alignment-tech-brief.html Intel® SSD Partition Alignment for Max Performance, Endurance

http://www.intel.com/content/www/us/en/solid-state-drives/ssd-dc-s3510-spec.html Intel® SSD DC S3510 Series Product Specification

http://download.intel.com/support/motherboards/server/sb/configuring_raid_for_optimal_perfromance_11... Configuring RAID for Optimal Performance on Intel systems

[DFrea]

Thank you for your answer. It helped....

I have one additional question. I don't know, if it belongs here, but... Do you also consider allocation unit size (cluster size)? Or do you keep it in default size (in case of NTFS)? I read different opinions on this, so I'm not sure.

Thank you...

[jbenavides]

The way to determine the best Allocation Unit size when formatting your drive is similar to the one required for the RAID Stripe size.

Since the Physical Sector Size of the SSD is 4KB, any unit with multiples of 4 KB will work fine for the SSD. In most cases the Default value will be OK.

You might need to change this if the drive will work in a specific task or configuration and the Software provider has specific recommendations about this, of if your RAID configuration has special requirements in this regards.