| Message ID | 1495642203-12702-4-git-send-email-felipe@nutanix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, May 24, 2017 at 05:10:02PM +0100, Felipe Franciosi wrote: > The bytes_xfer_now/prev counters are only used by the auto convergence > logic. However, they are used alongside the dirty_pages_rate counter, > which is calculated (and required) outside of this logic. The problem > with this approach is that if the auto convergence capability is changed > while a migration is ongoing, the relationship of the counters will be > broken. > > This moves the management of bytes_xfer_now/prev counters outside of the > auto convergence logic to address this issue. > > Signed-off-by: Felipe Franciosi <felipe@nutanix.com> Reviewed-by: Peter Xu <peterx@redhat.com> > --- > migration/ram.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/migration/ram.c b/migration/ram.c > index 495ecbe..1a3d9e6 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -697,6 +697,7 @@ static void migration_bitmap_sync(RAMState *rs) > /* calculate period counters */ > rs->dirty_pages_rate = rs->num_dirty_pages_period * 1000 > / (end_time - rs->time_last_bitmap_sync); > + bytes_xfer_now = ram_bytes_transferred(); > > if (migrate_auto_converge()) { > /* The following detection logic can be refined later. For now: > @@ -704,7 +705,6 @@ static void migration_bitmap_sync(RAMState *rs) > amount of bytes that just got transferred since the last time we > were in this routine. If that happens twice, start or increase > throttling */ > - bytes_xfer_now = ram_bytes_transferred(); > > if ((rs->num_dirty_pages_period * TARGET_PAGE_SIZE > > (bytes_xfer_now - rs->bytes_xfer_prev) / 2) && > @@ -713,7 +713,6 @@ static void migration_bitmap_sync(RAMState *rs) > rs->dirty_rate_high_cnt = 0; > mig_throttle_guest_down(); > } > - rs->bytes_xfer_prev = bytes_xfer_now; > } > > if (migrate_use_xbzrle()) { > @@ -730,6 +729,7 @@ static void migration_bitmap_sync(RAMState *rs) > /* reset period counters */ > rs->time_last_bitmap_sync = end_time; > rs->num_dirty_pages_period = 0; > + rs->bytes_xfer_prev = bytes_xfer_now; > } > if (migrate_use_events()) { > qapi_event_send_migration_pass(rs->bitmap_sync_count, NULL); > -- > 1.9.5 >
Felipe Franciosi <felipe@nutanix.com> wrote: > The bytes_xfer_now/prev counters are only used by the auto convergence > logic. However, they are used alongside the dirty_pages_rate counter, > which is calculated (and required) outside of this logic. The problem > with this approach is that if the auto convergence capability is changed > while a migration is ongoing, the relationship of the counters will be > broken. > > This moves the management of bytes_xfer_now/prev counters outside of the > auto convergence logic to address this issue. > > Signed-off-by: Felipe Franciosi <felipe@nutanix.com> Reviewed-by: Juan Quintela <quintela@redhat.com>
diff --git a/migration/ram.c b/migration/ram.c index 495ecbe..1a3d9e6 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -697,6 +697,7 @@ static void migration_bitmap_sync(RAMState *rs) /* calculate period counters */ rs->dirty_pages_rate = rs->num_dirty_pages_period * 1000 / (end_time - rs->time_last_bitmap_sync); + bytes_xfer_now = ram_bytes_transferred(); if (migrate_auto_converge()) { /* The following detection logic can be refined later. For now: @@ -704,7 +705,6 @@ static void migration_bitmap_sync(RAMState *rs) amount of bytes that just got transferred since the last time we were in this routine. If that happens twice, start or increase throttling */ - bytes_xfer_now = ram_bytes_transferred(); if ((rs->num_dirty_pages_period * TARGET_PAGE_SIZE > (bytes_xfer_now - rs->bytes_xfer_prev) / 2) && @@ -713,7 +713,6 @@ static void migration_bitmap_sync(RAMState *rs) rs->dirty_rate_high_cnt = 0; mig_throttle_guest_down(); } - rs->bytes_xfer_prev = bytes_xfer_now; } if (migrate_use_xbzrle()) { @@ -730,6 +729,7 @@ static void migration_bitmap_sync(RAMState *rs) /* reset period counters */ rs->time_last_bitmap_sync = end_time; rs->num_dirty_pages_period = 0; + rs->bytes_xfer_prev = bytes_xfer_now; } if (migrate_use_events()) { qapi_event_send_migration_pass(rs->bitmap_sync_count, NULL);
The bytes_xfer_now/prev counters are only used by the auto convergence logic. However, they are used alongside the dirty_pages_rate counter, which is calculated (and required) outside of this logic. The problem with this approach is that if the auto convergence capability is changed while a migration is ongoing, the relationship of the counters will be broken. This moves the management of bytes_xfer_now/prev counters outside of the auto convergence logic to address this issue. Signed-off-by: Felipe Franciosi <felipe@nutanix.com> --- migration/ram.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)