I recently purchased and configured a Dell R320 with 3 x 2.0Tb Western Digital SATA Hard drives and although I knew the Cachecade drive I had configured was working I did a quick performance comparison using HD Tune to confirm it and see the difference.
I don’t really think synthetic tests like this provide much value and it is easy to feel the difference in responsiveness when using the server in anger.
Just a quick bit of background on the server and specification:
Dell PowerEdge R320
Intel Xeon E5-1410 (2.80GHz, 10M Cache, 6.4GT/s QPI, Turbo, 4C, 80W)
3 x 2.0Tb Western RE Digital SATA hard drives (Configured as RAID 5)
PERC H710 512Mb NV Cache
Intel SSD DC S3500 Series 240Gb
The interesting thing which I did not realize until I started playing with this Dell Poweredge R320 is cachecade is now supported on the Dell H710 512Mb PERC controller and not just the 1Gb version. On the previous models (H700) the Cachecade options were only available on the 1Gb version which was a shame because it was one of the more expensive options when configuring a Dell PowerEdge.
In case you were wondering, the PERC H700 and H710 recognize and work perfectly well with the Intel DC S3500 Series Solid State Drives and they can be used either as cachecade volumes or regular volumes.
I didn’t purchase any of the drives or SSD from Dell when purchasing the server as they were too expensive and didn’t provide the options I wanted.
I know lots of websites provide extremely detailed performance analysis and I am not going to do that, I do not have the knowledge or the time to perform such exhaustive tests!
Dell Cachecade performance comparison
So, here are the figures obtained without Cachecade enabled:
and here with Cachecade enabled:
As you can see in the screenshot with Cachecade enabled that the performance is much more consistent with far fewer extreme spikes. Minimum speed is maintained at over 200MB/second which I think is pretty quick for a modest server. Although the Burst rate is lower which I don’t really understand.
I had stopped using RAID 5 in recent years due to the relativly poor performance, but I think that with the help of Dell Cachecade it could become more viable.
On the next server I will test RAID 10 without Cachecade vs RAID 5 with Cachecade on a simple 4 disk setup and see how they compare.
Tests were run on a cleanly installed Windows 2012 Standard Server.