Virtual Linx Servers on vMware Hypervisor - Performance Best Practice

[Alzhy]

We're testing the waters hosting some small to mid-sized Oracle DBs on Linux under vMware. Our DBA is claiming performance is horrible that the system seem to freeze during massive I/O (disk or network) activities.

Our disks are virtual disks allocated from an EVA array. It is possible the disks allocated from the vMware disk pool may have been carved from the same disk pool allocated for the OS and data of other virtual machines.

I am thinking perhaps directly presenting SAN disks to the Linux virtual machines -- via virtual FC-HBAs (NPIV). I am not sure though how vMotion will be affected doing so but I believe perhaps will be topnotch. Also, I am thinking of carvig DB disks out of vMware disks exclusivly for DB serving and not shared with the other VMs.

Any thoughts or Linux on Vmawre best practices? We're looking at using KVM but not if the people with vMware vested interests can help it.

We're using vSPhere btw.

[Steven E. Protter]

Shalom,

Oracle will perform well in an EVA environment, running in a virtual machine. If there is extremely high write volume, you might want to configure the EVA disk to RAID 1 or RAID 10 instead of Raid 5.

I/O is what you need to look at. You need to carefully plan your I/O to disk with your vmware environment.

Something to consider though is that vmware does add additional overhead. What is the difference between operating 4 vmware servers to supply 4 database instances versus one larger, more powerful machine running 4 instances.

You might want to run a pilot and test performance.

KVM or Xen will work as well as vmware. Oracle is not thrilled and occasionally denies support to vmware issues, but usually they just handle the cases normally.

I/O planning will get you good results if you want to save money with KVM or Xen.

SEP