diff options
| author | Lidong Chen <jemmy858585@gmail.com> | 2017-03-15 11:37:33 +0800 |
|---|---|---|
| committer | Juan Quintela <quintela@redhat.com> | 2017-03-16 08:58:27 +0100 |
| commit | 1cf6aa74b32f18f9b5faf525a93b0c1f609acb1f (patch) | |
| tree | 2dec61809940e38c6dee28f8aaf41122f80cbc18 | |
| parent | 4af245dc3e6e5c96405b3edb9d75657504256469 (diff) | |
migration/block: Avoid invoking blk_drain too frequently
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 <jemmy858585@gmail.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
| -rw-r--r-- | migration/block.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/migration/block.c b/migration/block.c index 6741228200..7734ff728a 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; |