Commit d2a4d85a authored by Felipe Franciosi's avatar Felipe Franciosi Committed by Juan Quintela
Browse files

migration: set bytes_xfer_* outside of autoconverge logic 



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: default avatarFelipe Franciosi <felipe@nutanix.com>
Reviewed-by: default avatarPeter Xu <peterx@redhat.com>
Reviewed-by: default avatarJuan Quintela <quintela@redhat.com>
Signed-off-by: default avatarJuan Quintela <quintela@redhat.com>
parent d693c6f1

migration/ram.c

+2 −2
Original line number Diff line number Diff line
@@ -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);