VMware Cloud Community
TimothyGaray
Contributor
Contributor

Oracle Runaway Process Consumes All vCPUs

A question was posed to us by our DBAs in regards to Oracle 10g running in a VM.

When the server was physical, if one Oracle process took off, it did not chew up all available computing resources - just the CPU that the particular process was running on.

Now that the server is virtual, if an Oracle process takes off, it chews up both vCPUs doing whatever.

We were considering giving it 4 vCPUs but their concern is that if someone submits a huge query then it will just consume 4 vCPUs at 100%.

Does anyone have any thoughts or experience with this? I'm not very familiar with Oracle.

Thanks!

-Tim

Reply
0 Kudos
4 Replies
aandriolli
VMware Employee
VMware Employee

There is no reason for a process using only one CPU core in a physical server to make use of two vCPUs in a VM. The ESX virtualization does not affect application behavior.

Can you check if your operating system inside the VM is using the proper HAL? If its Windows, it should be using a multiprocessor HAL, since you have 2 vCPUs, for instance. HAL issues tend to cause quite weird behaviors.

br>
[VMs Made in Brazil|http://communities.vmware.com/blogs/aandriolli]

PS: por favor considere dar pontos a este ou qualquer outro post caso lhe seja útil.

[VMs Made in Brazil|http://communities.vmware.com/blogs/aandriolli] PS: por favor considere dar pontos a este ou qualquer outro post caso lhe seja útil.
Reply
0 Kudos
TimothyGaray
Contributor
Contributor

I checked: ACPI Multiprocessor PC

I've got additional monitoring turned on and am waiting for "it" to happen again. If/when that happens, hopefully we will have more information as to what is going on.

-Tim

Reply
0 Kudos
petedr
Virtuoso
Virtuoso

Interesting one, I hadn't seen that actity before. Any thoughts I'll post back,

www.phdvirtual.com, makers of esXpress

www.thevirtualheadline.com www.liquidwarelabs.com
Reply
0 Kudos
TimothyGaray
Contributor
Contributor

Yes, I'm not sure why it would behave differently between a physical machine and a VM but the DBAs swear it does this. I'm hoping to see it and then maybe gain a little better understanding of what is going on. I'm already at a disadvantage since I am more of a SQL Server man than an Oracle man so I have no idea what to even look at when it comes to what Oracle does.

-Tim

Reply
0 Kudos