> Sent: Tuesday, April 19, 2016 10:52 PM > To: Li, Liang Z; m...@redhat.com; quint...@redhat.com; > amit.s...@redhat.com; pbonz...@redhat.com; lcapitul...@redhat.com > Cc: peter.mayd...@linaro.org; james.ho...@imgtec.com; > ehabk...@redhat.com; k...@vger.kernel.org; qemu-devel@nongnu.org; > arm...@redhat.com; ag...@suse.de; borntrae...@de.ibm.com; > cornelia.h...@de.ibm.com; leon.al...@imgtec.com; aurel...@aurel32.net; > r...@twiddle.net > Subject: Re: [Qemu-devel] [PATCH QEMU 5/5] migration: Add the interface > for cache drop control > > On 04/19/2016 08:20 AM, Liang Li wrote: > > Whether drop the cache and drop what kind of cache depend on the > > Whether to drop the cache, and what kind of cache drop to perform, > depend ... > > > user, add the related qmp and hmp interface to query and set the cache > > control value. > > > > Signed-off-by: Liang Li <liang.z...@intel.com> > > --- > > > +++ b/qapi-schema.json > > @@ -612,11 +612,21 @@ > > # @x-cpu-throttle-increment: throttle percentage increase each time > > # auto-converge detects that migration is not > > making > > # progress. The default value is 10. (Since 2.5) > > +# @x-drop-cache: drop guest's page cache during live migration, the value > can > > +# be set to 0, 1, 2, 3. 1 means drop the clean page cache, 2 means > > +# drop the slab cache, 3 means to drop both clean page cache, 0 > means > > +# do not drop any cache. Drop cache can speed up live migration > > +# process and reduce the network traffic, the side affect is the > > +# performance impact to the guest, 1 is the recommended value for > > +# proper balance between speed and performance. The value only > takes > > +# affect when the virtio-balloon device are enabled and the guest > > +# has the related driver. The default value is 0. (Since 2.7) > > Absolutely not this interface. Make this an enum type, not a raw magic- > number integer type, where the user requests "x-drop-cache":"clean", "x- > drop-cache":"slab", and so on. >
The enum type looks better, thanks! Liang > -- > Eric Blake eblake redhat com +1-919-301-3266 > Libvirt virtualization library http://libvirt.org
