we have a storageserver (CentOS 6.4) with a dualport Intel 10G X520-2
A QSan P600Q-D316 Storage is configured with 8*SATA Drives raid 5 for test, connected trought a Cisco UCS 6100 Series Fabric Interconnect 10G Switch.
I formated the storage with ext4 defaults, one volume and got r/w rates about 10MB/s some up to 40MB/s …. VERY POOR….
So we returned the storage to our dealer and they tested the hardware and did some IO Meter Test with VMware ESXi 5.1 Server -> virtual Windows 2k8-R2 on the Qsan Storage.
The VM did some r/w IO Meter Benchmark up to 1000 MB/Sec. Better. Hardware looks o.k.
Than they installed a Windows 2k8-R2 server and attached the QSAN. The r/w speed is about 400-500 MB/s.
After that the dealer installed a CentOS 6.4 as I did and the r/w performance is back to our results …. up to 40MB/s ….
What the hell? Are the default driver and settings so bad? I know and researched a lot of tuning options like buffers, new drivers etc.
We did not check that for now, but are’nt there some defalut values and settings which apply as well to be much faster?
Or in other words, are some realy simple hints and suggestions to
a) debug / find the bottleneck and
b) to increase the performance to the same level as windows?
Thanks a lot for any help and feedback . G