[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH] xend: update cpu config option
* Ian Pratt <m+Ian.Pratt@xxxxxxxxxxxx> [2005-11-16 16:07]: > > The 'cpu' option in domain config files will pin VCPU0 of a domain. > > This is not as useful now that domains can have more than 1 > > vcpu. This patch changes 'cpu' to 'cpus' and takes a list of > > physical cpus the domains' vcpus can use and will pin the > > vcpus upon domain creation. > > > > cpus = [1] # this starts all domain vcpus pinned to CPU1 > > I think this patch is generally a good thing. Should we support cpu= as > backward compatible legacy option? I pondered that as well. No reason we can't. Some documentation should avoid any confusion. I'll rework the patch to support cpu=X and cpus=[]. > > > The list is circular, so in a domain with the following config: > > > > vcpus = 4 > > cpus = [0,3,7] # Use any of 0, 3, 7 for this domain. > > > > would see vcpus 0-3 pinned to cpus 0,3,7,0 respectively. > > Actually, although this is a reasonable syntax, I think we'll probably > interpret it differently in future when we have CPU load ballancing: I > think we'll want to list the set of CPUs that a given _domain_ can use > rather than pining individual CPUs. I think the list is already representative of that idea: this is a list of cpus that any of the vcpus in this domain can use. Currently without a load balancer we only get one go at vcpu to cpu allocation. Also, no reason we can't replace the current algorithm down the road with a call out to the load balancer which would supply the mappings. > However, I wander whether this should be a string so that we can list > e.g. cpus='0-3,5,^1' I like that notation better, but it opens up a few questions. Do you mean the commas to indicate which cpus each vcpu is allowed to use, or just a list of cpus the domain can use? Also, I take ^1 to mean any cpu, yes? I'll end up converting the string into a big list of possible cpus to use and for each vcpu pick a cpu and pin it there. -- Ryan Harper Software Engineer; Linux Technology Center IBM Corp., Austin, Tx (512) 838-9253 T/L: 678-9253 ryanh@xxxxxxxxxx _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-devel
|
![]() |
Lists.xenproject.org is hosted with RackSpace, monitoring our |