Performance testing the pmsApp with filebench – RAID 5

I finally managed to get the 3 node pmsApp running, although there are some odd issues relating to failover that I will need to investigate further.

I altered the methodology slightly this time, I decided to use a single guest and move it around to the various storage devices.

In addition to the pmsApp, I tested on our SAN array (M2000 storage works configured as RAID10) and direct to an ESX host disk. The direct to host results are better than last time, particularly the fileserver workload. The result for the 2 node pmsApp (RAID1) are displayed for convenience although they are the same as from last’s post.

varmail webserver fileserver randomwrite (100 MB file) randomread (100 MB file) webproxy
SAN 25.8 MB/s 25.45 MB/s 25.85 MB/s 76.1 MB/s 90.0 MB/s 15.3 MB/s
Direct 6.15 MB/s 3.9 MB/s 9.1 MB/s 48.12 MB/s 88.9 MB/s 3.2 MB/s
PMSARAID1 1.24 MB/s 6.83 MB/s 4.20 MB/s 13.63 MB/s 89.1 MB/s 1.5 MB/s
PMSARAID5 1.56 MB/S 12.86 MB/s 4.6 MB/s 15.2 MB/s 89.3 MB/s 4.41 MB/s

As might be expected the SAN array is miles faster than anything else, so I won’t mention anything else about it, I simply wanted to provide a comparison point.

Direct to host tests show a significant speed up on the fileserver workload over the results on last’s post. I don’t really have an explanation for this. The results were consistent, standard deviation of only 0.7 MB/s. The other workloads are faster but not as much. This is a better control test, though, as it was exactly the same guest.

There is still the mystery of the webserver workload, which has now been amplified by the 3 node pmsApp, which triples the performance of the direct to host configuration.

The good news is that the 3 node pmsApp is faster than the 2 node. This shouldn’t be all that surprising as now it is only the parity data that needs to be written across the network rather than all data, so the results show a nice improvement throughout. Consistency has also improved, with standard deviation around 5%, except for the webserver workload.

I would love to compare the performance of the pmsApp to the actual VMware app, but I don’t have the hardware to do it. Not sure, whether the app will work with single disks.