Re: [Qemu-devel] [PATCH 1/8] migration: stop compressing page in migration thread

[Xiao Guangrong]

Hi David,

Thanks for your review.

On 03/15/2018 06:25 PM, Dr. David Alan Gilbert wrote:

> >   migration/ram.c | 32 ++++++++++++++++----------------
>
> Hi,
>    Do you have some performance numbers to show this helps?  Were those
> taken on a normal system or were they taken with one of the compression
> accelerators (which I think the compression migration was designed for)?

Yes, i have tested it on my desktop, i7-4790 + 16G, by locally live migrate
the VM which has 8 vCPUs + 6G memory and the max-bandwidth is limited to 350.

During the migration, a workload which has 8 threads repeatedly written total
6G memory in the VM. Before this patchset, its bandwidth is ~25 mbps, after
applying, the bandwidth is ~50 mbps.

BTW, Compression will use almost all valid bandwidth after all of our work
which i will post it out part by part.