On Thu, Aug 28, 2008 at 04:30:55PM +0100, Richard W.M. Jones wrote: > On Thu, Aug 28, 2008 at 10:58:34AM -0400, Cole Robinson wrote: > > Last month you had brought up the idea of a unified api call to > > lookup all domains, with a flag option to filter the lookup by > > domain state: > > > > https://www.redhat.com/archives/libvir-list/2008-July/msg00215.html > > It's worth making clear that the key issue isn't the filtering, but > the fact that the virConnectListDomains & virDomainLookupByID calls > would be combined. This is a big saving in the remote case too > because it turns 1+N round-trips into 1 round-trip. > > Virt-manager and virt-top both make these 1+N calls frequently (as in, > once a second, and once every 3 seconds respectively). Yes, this is a huge performance win when talking to XenD since each XenD RPC call to list domains is ~ 0.5-1 second or worse. > Also, if we use the __virDrvSupportsFeature call then we can actually > emulate it in src/libvirt.c for drivers / libvirtd instances which > don't understand the new call. This means that applications can use > the new call immediately, with confidence that it will work for all > cases. Good idea - that hadn't occurred to me - it'll be useful for talking to old libvirtd instances at the very least - implementing the new style for built-in drivers should be trivial already. Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :| -- Libvir-list mailing list Libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list