On Tue, 2015-09-29 at 15:18 -0600, Mike Latimer wrote: > Hi Ian, > > On Tuesday, September 29, 2015 10:25:32 AM Ian Campbell wrote: > > On Mon, 2015-09-28 at 17:14 -0600, Mike Latimer wrote: > > > Any better options or ideas? > > > > Is part of the problem that shell is a terrible choice for this kind of > > check? > > There is some truth to that... ;) > > > Would shelling out to a helper utility allow this to be written in > > something better? > > A helper utility would be useful, however, I'm seeing a huge amount of gain > with nothing more than a little code motion. Specifically, if shared_list is > generated within the check_sharing function, the (potentially) large list of > devices is not too painful to work with. > > For example, the attached patch works well in my environment, and removes the > exponential slowdown. The main change is that $devmm becomes a comma > delimited > list of devices (major:minor) to check against the vbd's found in xenstore. A > few minor changes are required along the way, but nothing significant. The > comma delimited list might become problematic at very large numbers > (hundreds) > of a single shared device, but I don't think it will be a problem in > practice. > Even if it has limitations, this approach offers significant improvements in > performance. > > I'll continue to test this patch here, but I'm interested in your opinion.
If you have a patch which improves things then I think you should just go ahead formally submit it (http://wiki.xen.org/wiki/Submitting_Xen_Patches). Ian. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel