Hello!

I have held testing and find out that PVSCSI  adapter performance is not fine like I want.

Platform: ESX 4.0 evaluate on Intel SR2500 with Xeon 5420, 32GB RAM and SRCSASRB RAID controller with 3 SATA (Seagate 500GB) drives in 5RAID.

There is single VM on this host: Win 2003 x64 Std with 8Gb RAM and 2 CPU.

I used SQLIO tool for my tests:

sqlio -kR -s120 -frandom -o8 -b8 -LS -Fparam.txt

param.txt is one string - e:\testfile.dat 2 0x0 512

First test:

One boot hard disk on LSI Parallel SCSI controller (SCSI 0:0) and one tested drive(NO independent) on PVSCSI  adapter (SCSI 1:0).

Results:

IOs/sec:   503.25

MBs/sec:     3.93

latency metrics:

Min_Latency(ms): 0

Avg_Latency(ms): 31

Max_Latency(ms): 924

Second test:

One boot hard disk on LSI Parallel SCSI controller(SCSI 0:0) and one tested drive(independent and persistent as here http://kb.vmware.com/selfservice/viewContent.do?externalId=1010398&sliceId=1) on PVSCSI  adapter(SCSI 1:0)

Results:

IOs/sec:   499.71

MBs/sec:     3.90

latency metrics:

Min_Latency(ms): 0

Avg_Latency(ms): 31

Max_Latency(ms): 763

Third test:

One boot hard disk on LSI Parallel SCSI controller(SCSI 0:0) and one tested drive on another LSI Parallel SCSI controller (SCSI 1:0).

IOs/sec:   614.19

MBs/sec:     4.79

latency metrics:

Min_Latency(ms): 0

Avg_Latency(ms): 25

Max_Latency(ms): 704

Performance of LSI Parallel SCSI controller is greater then  PVSCSI! Somebody knows why so?