high hardware CPU interruption on Windows 2003

[mephistopoa]

Hi guys,

I've several virtual machines running windows 2003 and citrix presentation server 4.5 and I'm experiencing high cpu interruptions on the virtual machine like 30-40% of the cpu time, so if the cpu is 20% busy, it is almost 20% on top of that of interruption time.

I've created a new VM from scratch, tried more vcpus, cloned a physical (I know this is what can cause, but just for testing) and several other things.

The performance is being very erratic, sometimes the graph bellow is red all the way. It must be a problem with a CPU scheduler or something. Could you guys please give me some advice? Thanks!

[mephistopoa]

Hi guys, any tip is welcome please

[shishir08 · Accepted solution]

CPU utilization increases when a system process requires more time  or  when more network packets are sent and received. The CPU becomes  too  busy when the CPU receives too many packets from the switch  hardware or  when a system process consumes too much CPU time. When  either of these  functions uses CPU resources then it will be  the  detriment to the  other,  because the CPU is too busy.  For example, if  the CPU is  receiving many packets  because of a broadcast storm on the  network, it  is so busy processing all the those packets that the other  system  processes do not have access to CPU resources.

Just check whether CPU is busy in processing the network packets.

HTH

[mephistopoa]

You are right in this aspect, but this never happened on physical servers running P4 xeons, they were busy all the time but not with interruptions, just normal work load. The host is using no more than 35% of its CPU 2x 6 core xeon during the busy hours, so I can't see the CPU as being the bottleneck here.

How could I check the cpu usage only for network resources?

Thanks for your tips

[mephistopoa]

Just a bump, still not resolved