Re: VM Host Hardware Recommendations.
Garth Boyd <[email protected]>
| Newsgroups | gmane.user-groups.linux.ottawa.general |
|---|---|
| Message-ID | <CAK8NDnqyPiDusUQV5Y+eBcBU=Ty29O=ShqFNC5OicfS7drnjqw@mail.gmail.com> |
Thanks. All this is helping my understanding. I am wondering if there are any stock boxes out there with a CPU that has many cores and serious cache that I could use to save building my own box. Is anyone aware of any candidates? G On 28 July 2011 09:29, Aaron WIlcox <[email protected]> wrote: > All of the Intel Core i3/i5/i7 CPUs have the Intel VT-x extensions, so you > don't necessarily have to get a server CPU to do full hardware > virtualization. > > > On 11-07-26 09:37 AM, Bart Trojanowski wrote: > >> First and foremost you need a CPU with hardware virtualization >> extensions. I am taking this for granted because it's hard to find a >> server class CPU w/o this. >> >> As Brad pointed out, it's hard to give specific advice until you know >> the I/O vs CPU vs memory load. However, I can give you some general >> advice. >> >> There are three things I look for when building hosts for virtualization: >> >> - cache >> >> Having a large CPU cache means that context switches (in this case >> from one VM to another) are not as costly. It also reduces the >> contention on the memory bus, which is a shared between multiple VMs. >> >> - RAM >> >> Naturally more RAM allows you run more VMs... but more importantly >> having lots of RAM prevents the need to go to disk to get data as it >> can be cached. Having free RAM around can improve certain kind of >> disk I/O loads. This is true on non-virtualized systems as well. >> >> - cores >> >> If you have a lot of active VMs, the system will spend a lot of time >> ushering VMs in and out of the CPU. This wastes time, and having more >> cores helps. Be careful here... adding cores without adding to the >> CPU cache can make things worse. >> >> After these, thing get expensive. You can pin dedicated network cards >> to each VM to improve network I/O. You can also improve your storage >> I/O bandwidth by using a SAN. >> >> -Bart >> > > -- > > > Aaron Wilcox > > GMail <mailto:aaron.s.wilcox@gmail.**com <[email protected]>> > Sympatico <mailto:aaron.wilcox@**sympatico.ca <[email protected]>> > > -- > OCLUG general discussion list > [email protected] > http://oclug.on.ca/mailman/listinfo/oclug > > -- - Garth -- OCLUG general discussion list [email protected] http://oclug.on.ca/mailman/listinfo/oclug