On Fri, Feb 09, 2018 at 11:11:39AM +0800, Wei Wang wrote: > On 02/09/2018 03:55 AM, Michael S. Tsirkin wrote: > > On Thu, Feb 08, 2018 at 05:50:16PM +0800, Wei Wang wrote: > > > > > Details: > > > Set up a Ping-Pong local live migration, where the guest ceaselessy > > > migrates between the source and destination. Linux compilation, > > > i.e. make bzImage -j4, is performed during the Ping-Pong migration. The > > > legacy case takes 5min14s to finish the compilation. With this > > > optimization patched, it takes 5min12s. > > How is migration time affected in this case? > > > When the linux compilation workload runs, the migration time (both the > legacy and this optimization case) varies as the compilation goes on. It > seems not easy to give a static speedup number, some times the migration > time is reduced to 33%, sometimes to 50%, it varies, and depends on how much > free memory the system has at that moment. For example, at the later stage > of the compilation, I can observe 5GB memory being used as page cache. But > overall, I can observe obvious improvement of the migration time. > > > Best, > Wei You can run multiple tests and give a best, worst and median numbers. -- MST
