perfomance

slavik · Wed May 12, 2010 12:02 pm

hello
i have strange very low perfomance, i have 1 esxi 4.0u1 (build 244038) on sun x4100 and starwind (5.3.0.1310) at windows 2003r2 x64 running on sun x4600, when i xmit data over gigabit copper i have about 3 meg per second even if device is ramdrive

Constantin (staff) · Thu May 13, 2010 8:46 am

test your network please using iperf or NTTTCP

slavik · Thu May 13, 2010 9:07 am

already, looks like this is esxi4 problem instead of starwind bug.
good perfomance inside vm with microsoft initiator, and poor from host.

Constantin (staff) · Thu May 13, 2010 9:23 am

OK... What build of ESX do you use and what NICs?

slavik · Thu May 13, 2010 12:22 pm

"...esxi 4.0u1 (build 244038) on sun x4100..."
onboard 1 intel pro 1000 mt dual port server, broadcom n/c

Constantin (staff) · Mon May 17, 2010 9:00 am

That`s strange... Have you find ant reason of this problem?

slavik · Mon May 17, 2010 10:09 am

no, i suggest this esxi4 perfomance problem is irq-flood related. Because i found similar problem with iscsi target based on freebsd (istgt). But there is much less perfomance penalty, native 30MB/s down to 10MB/s via gigabit iscsi, with starwind speed penalty native 90MB/s down to 3MB/s.

slavik · Wed May 19, 2010 12:13 pm

up: this (3MBps) poor perfomance didn't stable, sometimes it raises up to 15-50MBps.
anyway this is much less than raw perfomance from SAS stripe (85 to 110 MBps)

Wed May 19, 2010 3:22 pm

If you have the same degradation picture with other iSCSI target I'd suggest you to double-check ESX(i) iSCSI initiator settings and if approved OK check other hardware.

slavik · Thu May 20, 2010 4:05 am

anton, what settings exactly you suggest to check?
hardware is okey, this was checked already, and indirectly indicated by fact that inside VM iscsi initiator works much better

Thu May 20, 2010 3:56 pm

slavik
Please try connecting ESXi host directly to the StarWind server using a straight connection and reproducing the issue.

slavik · Fri Jun 11, 2010 5:55 am

max, "good perfomance inside vm with microsoft initiator, and poor from host." - this means if initiator inside VM i has nice speed, so I suggest this bug does NOT network related, but i can test straight connection speed next week

Constantin (staff) · Fri Jun 11, 2010 1:12 pm

So, please inform about result of test (direct connection w/o switch) in datacenter.