Core 0, Socket 0

[bdseymour]

I have a standalone server that I am setting up as a test box for vmware 5. I need to configure vmware to not share core 0 on socket 0. is that done through resources, advanced cpu and then I would set the virtual machine to not use 0?

[weinstein5]

Curious as why you would want to do this? The vmkernel does a great job of scheduling cpu resources and removing a core from themix can limit the number of VM and eprformanc eyou will be able to host -

[bdseymour]

okay, so this is coming from the programmers. they want to make sure that their SQL install is not using the core, socket as vmware for testing.

[weinstein5]

I do not recommend it but you could set the CPU affinity for the VM restricting the VM to run on all other LCPU other than CPU0

[bdseymour]

so I have 24 logical CPUs. I would set "2-24" since 1 and 2 are both on core 0?

[weinstein5]

That is correct - but to be honest the programmers will notice no difference in performance whether affinity is set or not -

[bdseymour]

I meant 3-24

[bdseymour]

Is that set with quotes "3-24". I ahve DRS turned off on the clsuter. Also do I have to reboo the box?

[weinstein5]

I believe that is correct - no you do not have to reboot the VM -

[bdseymour]

So this server has 2 processors with 6 cores so 12 CPU Cores. Is there a simple way of mapping core to cpu? so I can evenly distrubte between waht is left?

[weinstein5]

yes - you had guessed correctly  LCPU 0-5 are the cores on physical CPU 0 and if HT is available and enabled then it would be LCPU 0-11. So you can see you will be forcing the VM to run on a single physical CPU -

Seeing it written I striongly you urge not to do this I see the potential for the VM to be constrained by CPU and something else to consider by setting CPU affinity will prevent vmotion and will not allow you to use DRS

I am also going to move this thread to a more approriate forum

[bdseymour]

Well i also have to take into account the Hyperthreading whcih give 24 logical cpus so i actually ahve to say 4,6,8,10,12,14,16,18,20,22 to spread evenly

without using cpu0 and core 0

[mcowger]

I have to agree with David - I'm not sure you understand how truly horrible of an idea this is....

[bdseymour]

I understand but it is just for testing purposes for the programmers.