I just set up a 5 node esx cluster running Qlogic 8142 CNAs connected to two Nexus 5000.
At first everything seemed fine but I then noticed strange performance issues when copying lagre amonts of data both from within VMs and at a host level, it will start copying data at full speed and then completely stop for 10-15sec before again resuming at full speed. This will go on until the datacopy completes. This behavior also causes timeouts on large DB queries.
I see a lot of pause frames in the Nexus switches, I dont know if this is normal or not?
Running IOmeter from a VM shows no sign of problem, it runs steady at max speed.
Anyone seen this behavior?
Nexus running latest firmware
Qlogic 8142 running latest firmware
ESX 5.0.0 using the following CNA drivers:
qla2xxx-911.k1.1-offline_bundle-472334.zip
qlge-1.0.0.47-offline_bundle-463318.zip
The disk system is a very basic one, IBM DS3524 with 96 drives