I have a big problem of performance with my customer configuration.
In fact we experienced very slow large files transfer rate from windows computers to windows servers VM: max transfer rate for a 2GB file is 15MB/s. I assume we must expect over 100MB/s transfer rate
We used an MSA2312i with 7 disks of 450GB 15k in RAID5, 2 HP DL360g7 servers with 12 NICS as ESX4.1 servers. For having a fault tolerance, we used 2 dedicated HPprocurve 1810G for connecting the 2 iSCSI NICS of ESX's and the 2 controllers of the MSA.
On the MSA we have 2 vdisks (1 of 2TB and 1 of 700GB)
Our 6 VMs are running on the 2TB VMFS datastore.
I made a lot of tests that puzzles me...
_ configuring software iSCSi : no change
_ using another switch: dlink DGS-3100: no change
_ using Write-back or Write-through caching on the MSA volume: no change
_ changing mutltipathing to round robin: no change
_ changing NICS used for software iSCSI: no change
_ installing another ESX server (different hardware) in VMWARE ESX4.0, migrating a VM to this host: no change
_ migrating a VM in the local ESX datastore: WHAOOOOO!!! transfer rate between 50MB/s and 80MB/s
_ configuring a server Windows 2008 ( physical) with software initiator on the MSA2312i using the same switch than ESXs. I formatted the 700GB vdisk from VMFS to NTFS in order to show it on the server: WONDERFUL, I copy a 2GB file at 80M/s in less than a minute!!!
With those tests, I know that MSA is good because in windows iSCSi environnment I have no problem. But I can't explain why in Vmware environment I experienced a such poor performance?!
Any help or any idea on this case will be really appreciated!
For information, my VMWARE case is opened since 24/12/2010!!! and not closed at this time.
An HP case was closed since a month because of our test with the windows server 2008!!!
I'll give you any further information if needed!
Thanks in advance,