Enable hyperthreading for virtualized Oracle 11gR2 database (OEL57)?

[FredMcDonald]

We are virtualizing our Oracle 11gR2 databases (running on OEL57 64-bit) on Vmware 5.1.   I've read information at various locations that hyperthreading is not recommended for Oracle 11g database.  One example is here, however, I seen many more:

http://bryangrenn.blogspot.com/2011/08/hyperthreading.html

My issue is that Vmware themselves recommend enabling hyperthreading for virtalized Oracle databases in their Oracle Databases on VMwareBest Practices Guide.

Does anyone have any practical expierence with this issue that can be shared?  What are the advantages and disadvantages of enabling hyperthreading for our virutalized Oracle 11gR2 on OEL57 64-bit virtual machines

Thanks, Fred

[cainics]

I have in the past virtualized an Oracle ERP database successfully on VMware and hyperthreading was turned on.  In my experience, there was no problem and we didn't see any negative performance. The database was moved from a unix OS to RHEL. My experience also indicated some performance factors that were affected due to CPU reservations and limits if set.

Note that the virtualization was done on vSphere 4.2 and not the latest vSphere 5.1. I can run a test in my lab and come back to you with the test results. If you have a test environment already you can simulate the test as well and find out if hyperthreading is affecting or helping with the latest versions.