expected_downtime value is not accurate with dirty_pages_rate * page_size,
using ram_bytes_remaining() would yeild it resonable.
consider to read the remaining ram just after having updated the dirty
pages count later migration_bitmap_sync_range() in migration_bitmap_sync()
and reuse the `remaining` field in ram_counters to hold ram_bytes_remaining()
for calculating expected_downtime.
Reported-by: Michael Roth <mdr...@linux.vnet.ibm.com>
Signed-off-by: Balamuruhan S <bal...@linux.vnet.ibm.com>
Signed-off-by: Laurent Vivier <lviv...@redhat.com>
---
migration/migration.c | 3 +--
migration/ram.c | 1 +
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/migration/migration.c b/migration/migration.c
index ea9a6cbb87..cb14dadb26 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -2739,8 +2739,7 @@ static void migration_update_counters(MigrationState *s,
* recalculate. 10000 is a small enough number for our purposes
*/
if (ram_counters.dirty_pages_rate && transferred > 10000) {
- s->expected_downtime = ram_counters.dirty_pages_rate *
- qemu_target_page_size() / bandwidth;
+ s->expected_downtime = ram_counters.remaining / bandwidth;
}
qemu_file_reset_rate_limit(s->to_dst_file);
diff --git a/migration/ram.c b/migration/ram.c
index a500015a2f..a94a2b829e 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1159,6 +1159,7 @@ static void migration_bitmap_sync(RAMState *rs)
RAMBLOCK_FOREACH_MIGRATABLE(block) {
migration_bitmap_sync_range(rs, block, 0, block->used_length);
}
+ ram_counters.remaining = ram_bytes_remaining();
rcu_read_unlock();
qemu_mutex_unlock(&rs->bitmap_mutex);
--
2.14.3
