Re: [PATCH v28 0/4] Virtio-balloon: support free page reporting

From: Wei Wang
Date: Thu Feb 08 2018 - 22:09:26 EST


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