I''ve been looking around for information on how to size out a Xen machine. I don''t have any experience with Xen (making this a bit harder) and my old server is 512MB, and Xen won''t let me install a domU since I don''t have enough RAM. :-/ Anyway, I''m looking at a MythTV, database, webserver, fileserver, workstation, abd source code repository on my home server. About 6 virtual machines is what I think I''m seeing. The most intensive one will be the MythTV server. I''m guessing 4 cores and about 4GB plus a crap load of disk. But, I''m pulling numbers out of my backside. Will I want more? Xeon vs Core2 -- will that matter? I assume I''ll want 64 bit? I haven''t spotted anything to assist, but I''m sure its out there. Any help would be appreciated! Thanks! -Rob _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Rob Greene wrote:> I''ve been looking around for information on how to size out a Xen > machine. I don''t have any experience with Xen (making this a bit > harder) and my old server is 512MB, and Xen won''t let me install a > domU since I don''t have enough RAM. :-/ > > Anyway, I''m looking at a MythTV, database, webserver, fileserver, > workstation, abd source code repository on my home server. About 6 > virtual machines is what I think I''m seeing. The most intensive one > will be the MythTV server. I''m guessing 4 cores and about 4GB plus a > crap load of disk. But, I''m pulling numbers out of my backside. Will > I want more? Xeon vs Core2 -- will that matter? I assume I''ll want > 64 bit? > > I haven''t spotted anything to assist, but I''m sure its out there. > > Any help would be appreciated! > > Thanks! > -Rob > ------------------------------------------------------------------------ > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-usersHow many users will connect to it? What will the concurrent connections be? Generally, 5 / 6 VM''s per Core is fine, but the RAM all depends on how much RAM each VM needs. If you have 6 VM''s, and each needs 512MB RAM, then you need at least 3.5GB. which will leave you with 512MB for the Xen server itself. Don''t max out the RAM, try and leave some room if possible. Xeon is only really needed if you''re going to put heavy load on the server, many users connecting to it at the same time doing a lot of CPU stuff -- Kind Regards Rudi Ahlers CEO, SoftDux Web: http://www.SoftDux.com Check out my technical blog, http://blog.softdux.com for Linux or other technical stuff, or visit http://www.WebHostingTalk.co.za for Web Hosting stuff _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Thu, Apr 3, 2008 at 1:21 PM, Rudi Ahlers <Rudi@softdux.com> wrote:> How many users will connect to it? What will the concurrent connections > be? >Not that many -- 2 or 3 users max, really. I host a Subversion repository for a couple of other folks, and then my local network. Sounds like 4 cores would be ample. I''m not certain of load -- assuming that Xen itself doesn''t really add much, the load should be pretty low (if not idle) except when MythTV is processing video, and I was planning on limiting it to 2 CPUs, so again 4 cores should be just fine. I had kinda figured 256MB for the basic machines and then 512MB for a couple of them (MythTV and workstation), so my 4x256MB + 2x512MB memory sizing. But, maybe 512MB is the comfort spot for a Linux box... Which is good to know -- I''d rather spend my $$ wisely. :-) Thanks! -Rob _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
> On Thu, Apr 3, 2008 at 1:21 PM, Rudi Ahlers <Rudi@softdux.com> wrote: > > How many users will connect to it? What will the concurrent connections > > be? > > Not that many -- 2 or 3 users max, really. I host a Subversion repository > for a couple of other folks, and then my local network. Sounds like 4 > cores would be ample.Yes, I expect it really would be ample - especially if the VMs aren''t concurrently active most of the time. You could possibly get away with less, depending very much on what exactly you plan to do. Your 4 core CPU (I''m assuming you''re looking at Intel Core 2?) should have virtualisation tech, so as long as you don''t get a silly motherboard that disables it, full virtualisation should work too (i.e. Windows, amongst other things). Sounds like buying a Xeon would probably be overkill.> I''m not certain of load -- assuming that Xen itself > doesn''t really add much, the load should be pretty low (if not idle) except > when MythTV is processing videoWhat exactly are you doing with MythTV? Some folks have dedicated a PCI TV card to a VM and run Myth in that domain to record it, etc. That''s doable but obviously it''ll be simple if you''re just using Myth as a storage server or something - less faffing around. Works either way though.> and I was planning on limiting it to 2 > CPUs, so again 4 cores should be just fine. >You can limit a domain to a certain percentage of CPU time and to a certain number of concurrent CPUs, which should help.> I had kinda figured 256MB for the basic machines and then 512MB for a > couple of them (MythTV and workstation),When you say "workstation", do you mean that you''ll actually be logging into that domain on the physical terminal? If so, that domain will have to be dom0 (the master domain). This is unfortunate, security-wise, given that dom0 has control over all other domains. However, for a small home server (especially as you probably trust your home users!) I don''t think this''ll be a big problem - just something to be aware of. Also, if you''re using it as a workstation, you should consider your graphics set up. It can be a pain to get 3D graphics drivers working under Xen, so you should research this first.> so my 4x256MB + 2x512MB memory > sizing. But, maybe 512MB is the comfort spot for a Linux box... Which is > good to know -- I''d rather spend my $$ wisely. :-)Indeed! Cheers, Mark -- Push Me Pull You - Distributed SCM tool (http://www.cl.cam.ac.uk/~maw48/pmpu/) _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users