16 x 256GB Samsung 830 SSD Raid 6 with LSI 9266-8i Controller in a Dell R720 (16 Bay)

 

As a systems administrator it seems like I’m constantly battling IO contention and latency in our san and local storage environments. So As months roll by these new SSD drives keep getting cheaper and cheaper, offering better write wear and longer life spans for high write intensive environments, so finally I’m taking the plunge to begin converting our most intensive systems over to solid state.

In the process of exploring solid state disk the samsung 256GB 830 series really stuck out of the crowd. The 830 offers fantastic read and write latency and throughput as well as being one of the only SSD series on the market where both the flash and storage controller are by the same manufacture.

The main reason for chosing the samsung is this benchmark at extreme systems.

 

 

Update: 8/24/12

We ended up going back to the dell H710P after having a few issues with the uEFI bios not playing well with the controller at post.  Not to mention LSI webbios is a horrible pile of useless shit, this is 2012 why the hell do we have this prehistoric pile of crap UI on a raid controller.  Whoever at LSI approved that to be shipped on the cards should be forced to stand in a fire.

The H710P has dells lovely customized controller bios which is keyboard driven EASY to use and FAST to configure with.   Performance of the H710P is actually a little bit better than the 9266-8i while the hardware is identical.

Another major issue with the 9266 is when you would remove a drive *failure simulation* and replace it, the controller would mark the new drive as bad vs treating it as a fresh drive to rebuild on.  Without the CLI or MegaRaid Storage Manager this is a rather annoying problem to deal with as you would need to reboot the system to fix it in WEbiboss11!!111.. POS.

The H710P obviously works with dells unified system and can be accessed a number of ways without the operating system even knowing about it.

 The configuration:

  • 16x Samsung 830 256GB MLC SSD
  • Raid 6 with read and write caching (BBU backed).  64KB Block Size
  • Dell R720 16 Bay 8i SAS6 Expanded Backplane  2 Ports 16 devices.

The Benchmarks!

Here are some prelim benchmarks of the actual performance inside a VMware machine.

LSI 9266-8i

Children see throughput for 32 initial writers  =  214905.26 ops/sec
Parent sees throughput for 32 initial writers   =  198172.68 ops/sec
Min throughput per process                      =    6392.06 ops/sec
Max throughput per process                      =    7173.76 ops/sec
Avg throughput per process                      =    6715.79 ops/sec
Min xfer                                        =  925970.00 ops

Children see throughput for 32 readers          =  734057.97 ops/sec
Parent sees throughput for 32 readers           =  734011.56 ops/sec
Min throughput per process                      =   22833.85 ops/sec
Max throughput per process                      =   23062.16 ops/sec
Avg throughput per process                      =   22939.31 ops/sec
Min xfer                                        = 1038205.00 ops

Children see throughput for 32 random readers   =   55662.96 ops/sec
Parent sees throughput for 32 random readers    =   55662.71 ops/sec
Min throughput per process                      =    1730.88 ops/sec
Max throughput per process                      =    1751.76 ops/sec
Avg throughput per process                      =    1739.47 ops/sec
Min xfer                                        = 1036073.00 ops

Children see throughput for 32 random writers   =   19827.16 ops/sec
Parent sees throughput for 32 random writers    =   19090.45 ops/sec
Min throughput per process                      =     584.53 ops/sec
Max throughput per process                      =     663.61 ops/sec
Avg throughput per process                      =     619.60 ops/sec
Min xfer                                        =  967988.00 ops

Dell H710P

Children see throughput for 32 initial writers  =  489124.60 ops/sec
Parent sees throughput for 32 initial writers   =  435746.51 ops/sec
Min throughput per process                      =   14005.25 ops/sec
Max throughput per process                      =   17028.75 ops/sec
Avg throughput per process                      =   15285.14 ops/sec
Min xfer                                        =  860278.00 ops

Children see throughput for 32 readers          =  678563.56 ops/sec
Parent sees throughput for 32 readers           =  678524.72 ops/sec
Min throughput per process                      =   21111.18 ops/sec
Max throughput per process                      =   21253.53 ops/sec
Avg throughput per process                      =   21205.11 ops/sec
Min xfer                                        = 1041599.00 ops

Children see throughput for 32 random readers   =   59482.27 ops/sec
Parent sees throughput for 32 random readers    =   59482.00 ops/sec
Min throughput per process                      =    1851.91 ops/sec
Max throughput per process                      =    1869.25 ops/sec
Avg throughput per process                      =    1858.82 ops/sec
Min xfer                                        = 1038852.00 ops

Children see throughput for 32 random writers   =   20437.99 ops/sec
Parent sees throughput for 32 random writers    =   19228.06 ops/sec
Min throughput per process                      =     610.33 ops/sec
Max throughput per process                      =     695.63 ops/sec
Avg throughput per process                      =     638.69 ops/sec
Min xfer                                        =  945641.00 ops

 

 

Update 7/20/13!

So we’ve been running this configuration in production for almost a year now without fault.   Performance remains fantastic and we’ve had 0 disk failures or faults.

We’ve began testing on the 840 PRO series of disk and so far testing has not been as favorable, having some minor issues with 512gb drives being kicked from the array or faulting for no apparent reasons.

I can confirm that the 840 pro series are NOT compatible with the 24 bay chassis, the backplane power is designed for 12v utilization and the samsung drives are 5v.  You will have random system lockups with a message about not enough system power available.  If you need to populate a 24 bay chassis we recommend looking at the intel emlc drives which utilize 12v power optimization.