In order to test the sheer IOPS that this unit can pass along using a single raid controller we are going to the SanDisk ESS Lightning LS 300S drives. The maximum IOPS possible through the RAID controller that we have connected to the ARC-4036 is around 460,000 IOPS. There will be no cache used. Cache of a controller can typically blur true results that one is receiving from the enclosure or drives themselves. The RAID controller is using no cache whatsoever. This is pure IOPS, received from the enclosure by the controller itself, as the Lightning LS 300S series also does not have any cache.
The test is with three workers with the affinity forced over several cores to handle the load. Using Windows Server 2008 R2 we use a 8Gb test file at 512B with a Queue Depth of 32. Here we are pushing as hard as we can on the Random Read of four of these powerful drives in a RAID 0 configuration, using WidePort mode. The drives, controller, and definitely the ARC-4036 do not disappoint.
As you can see we are able to easily saturate the controller with the IOPS coming from the rear expander ports alone, 461,258 IOPS is certainly nothing to sneeze at! There is an impressive show of power there.
One must also bear in mind that this is the limit of the RAID controller, and NOT the enclosure. It is possible that many more IOPS could be passed through if we used multiple controllers, or future generations of controllers that can handle more. Here the RAID controller simply cannot give more. We have the enclosure configured with two SAS cables in “performance” mode.
Here we are exploring the difference of single port v the dual port usage of the enclosure. As you remember, the ARC-4036 can use one SAS cable to connect to the controller, or two SAS cables to enable the “Performance” mode of the enclosure, and maximum IOPS/Throughput. We can see that with only one SAS cable the enclosure pulls off a mighty 342,516 IOPS. This result shows that all but the most powerful users with daisy-chained enclosures will not need to connect with two SAS cables. This is a true testament to the power of the expander as we wouldn’t even want to speculate how many HDDs it would take to pull off that kind of IOPS performance.
NEXT: PATRIOT WILDFIRE RESULTS
~ CONCLUSION ~