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Web-Server, File-Server and Workstation Patterns

The drives are tested under loads typical of servers and workstations.

The names of the patterns are self-explanatory. The Web-Server pattern emulates a server that receives read requests only whereas the File-Server pattern has a small share of write requests. The request queue is limited to 32 requests in the Workstation pattern.

You can view all the graphs by clicking this link. We will be discussing only summary diagrams.

When there are only read (and mostly random-address) requests in the queue, most of the arrays look identically good. The difference is less than 5%. The type of RAID is rather unimportant as RAID6 is as fast as RAID0. There is only one important exception: RAID0 arrays are fast on those controllers that can effectively find the luckier disk in a mirror pair, i.e. on the 3ware, HighPoint and LSI.

The addition of write requests into the load makes the results more diverse. The RAID and RAID6 arrays are now slower than the RAID0 and RAID10. And we can also see the individual peculiarities of each controller. The 3ware and HighPoint are still the best with RAID10 (the LSI falls behind because its performance stops to grow up starting from a certain request queue depth as you can see in the graph). As expected, the Promise is much worse than the other controllers with checksum-based arrays. It is only with these arrays that the HighPoint is slower than the leaders.

The same goes for the Workstation pattern but the competition is tougher due to the increased share of writes and the different order of requests in the load. As a result, the Areca wins with RAID0 whereas the HighPoint and 3ware are still better than the others with RAID10. The HighPoint and Promise fall far behind the leaders with RAID5 and RAID6.

When the test zone is limited to 32GB (i.e. to the fastest tracks of the HDDs), the standings are different. For example, the LSI and Promise are obviously slow with RAID0. The advantage of the 3ware and HighPoint with RAID10 shrinks to a minimum: it is not important to choose the luckier disk anymore because the response time is low everywhere. The Promise falls behind with RAID10, too. The overall performance of the controllers is higher with RAID5 and RAID6 but the HighPoint and Promise are still lagging behind the leaders.

 
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