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I am running JBoss on both a physical machine, and a VM that runs within that same physical machine. The JBoss instance on physical machine is operating fast, but the JBoss on VM is slow (several orders of magniture). It appears that the following operations on the VM are slow: SVN checkout, big data streams (from database or external systems), hibernate calls. CPU and Memory % appears to be good on teh virtualization console.

I would therefore assume that the bottleneck is either 1) disk IO access, or 2) network. The disk that the VM uses resides on the same machine as the physical machine, and the VM is in the same network as the physical machien (ofcourse different IP).

Any ideas where I should begin to look at? Thanks

share|improve this question
if you're using RHEV, have you tried to call techsupport? – dyasny Jan 7 '14 at 16:31
You realize that a virtual machine will never be as fast as a physical machine, right? – mdpc Jan 7 '14 at 16:46
No I haven't called. I do understand VM:s can be slower, but not 4x slower :) I tested again when more testers are using the VM and it is even slower, although CPU and Memory are roughly the same. Maybe something with disk writes... – user1340582 Jan 8 '14 at 6:51
Hmm for some reason my Jenkins unit tests raise the java CPU % to over 100%. Since RHEV manager/agents apparently run on Java, this could have an impact. – user1340582 Jan 8 '14 at 8:39
RHEV Manager (engine) runs on Java, the guest agent doesn't. – dyasny Mar 5 '14 at 21:10

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