Fam Zheng <f...@redhat.com> wrote: > On Wed, 03/15 17:31, Dr. David Alan Gilbert wrote: >> * Fam Zheng (f...@redhat.com) wrote: >> > On Wed, 03/15 11:37, Lidong Chen wrote: >> > > Increase bmds->cur_dirty after submit io, so reduce the frequency >> > > involve into blk_drain, and improve the performance obviously >> > > when block migration. >> > > >> > > The performance test result of this patch: >> > > >> > > During the block dirty save phase, this patch improve guest os IOPS >> > > from 4.0K to 9.5K. and improve the migration speed from >> > > 505856 rsec/s to 855756 rsec/s. >> > > >> > > Signed-off-by: Lidong Chen <jemmy858...@gmail.com> >> > > --- >> > > migration/block.c | 3 +++ >> > > 1 file changed, 3 insertions(+) >> > > >> > > diff --git a/migration/block.c b/migration/block.c >> > > index 6741228..7734ff7 100644 >> > > --- a/migration/block.c >> > > +++ b/migration/block.c >> > > @@ -576,6 +576,9 @@ static int mig_save_device_dirty(QEMUFile *f, >> > > BlkMigDevState *bmds, >> > > } >> > > >> > > bdrv_reset_dirty_bitmap(bmds->dirty_bitmap, sector, >> > > nr_sectors); >> > > + sector += nr_sectors; >> > > + bmds->cur_dirty = sector; >> > > + >> > > break; >> > > } >> > > sector += BDRV_SECTORS_PER_DIRTY_CHUNK; >> > > -- >> > > 1.8.3.1 >> > > >> > >> > Nice catch above all, thank you! >> > >> > Reviewed-by: Fam Zheng <f...@redhat.com> >> >> Are you taking that via a block pull? > > I can do that, but I'm not sure whether it should go to 2.9. This is a > performance improvement, which usually doesn't qualify as bug fixes. But this > also looks like a mistake in original code. > > Fam
I am taking it through migration and push it. I agree with your description.
