vMotion of tomcat app server results in high CPU with vmmemctl and 6Gb more free memory

[fletch00]

Hi, I'm wondering if someone else has seen this during a vMotion of a CentOS 5 tomcat server (running 6 tomcat containers)

source host: Dell R900 Intel Xeon E7450 ESX 4.1 260247

dest host: Dell R610 Xeon 5680 ESXi 4.1 260247 (new)

I vMotion'ed the first of 2 Centos 5 VMs from the source to dest while running top and observed an unusual lag in top refresh during the cutover.

after about 15 seconds of no refreshes the VM came back and top showed a high load average with the vmmemctl near the top.

I also observed the "mem used" column on this 8Gb VM went from 7.9Gb to 2.4Gb in the span of 10-40 seconds!

Can someone explain why a vMotion operation would seem to cause the vmmemctl behave this way?

thanks

VCP4

[fletch00]

Turns out the memory allocation was increased, but the memory was limited

< sched.mem.max = "8192"

---

> sched.mem.max = "2048"

See http://www.vmadmin.info/2010/11/vmotion-high-cpu-vmmemctl.html

For how to debug this

thanks

VCP4