Storage vMotion performance dependency

[AGDave]

Hi,

This is in a test environment at the moment. I have a host with 1Gb nics to a 1Gb SAN, and a 10Gb NIC to a 10Gb SAN. Both are using iSCSI.

Both arrays are pretty much idle and use a number of 15k SAS disks.

I'm attempting to Storage vMotion a 10GB thick provisioned VM from the 1Gb SAN to the 10Gb one, this takes about 30mins which seems unusually slow to me.

Weirdly, if i storage vMotion the other way, ie 10Gb to 1Gb SANs, it takes only 1 minute.

esxtop reveals some really hih DAVG/cmd times for the 1Gb volume during this migration, such as 3000+.

Switch infrastructure is configured as per best practice, jumbo frames, flow control on, unicast storm control disabled.

Any ideas where I should look next?

Thanks,

[wtreutz]

Hi,

does you had configured the iSCSI vmkernel Stack in the right / correct way ..... sorry.
I had seen at a customer site for me sound´s like equal effects. The issues in this term was an incorrect vmkernel iSCSI Stack configuration.
The customer has the "same error" on all the ESXi-Host, im my example.

The customer has the effect

- slow virtual machine performance all the time

- check in ESXi ESXTOP see all time long latency on the vmkernel iSCSI Stack -- like your DAVG-value

reconfigure the vmkernel iSCSI Stack, the effect gone/was fixed.