On Fri, Mar 19, 2021 at 05:52:47PM +0300, Andrey Gruzdev wrote:
Added missing qemu_fflush() on buffer file holding precopy device state.
Increased initial QIOChannelBuffer allocation to 512KB to avoid reallocs.
Typical configurations often require >200KB for device state and VMDESC.
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
---
migration/migration.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/migration/migration.c b/migration/migration.c
index ca8b97baa5..32b48fe9f5 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -3812,7 +3812,7 @@ static void *bg_migration_thread(void *opaque)
* with vCPUs running and, finally, write stashed non-RAM part of
* the vmstate from the buffer to the migration stream.
*/
- s->bioc = qio_channel_buffer_new(128 * 1024);
+ s->bioc = qio_channel_buffer_new(512 * 1024);
qio_channel_set_name(QIO_CHANNEL(s->bioc), "vmstate-buffer");
fb = qemu_fopen_channel_output(QIO_CHANNEL(s->bioc));
object_unref(OBJECT(s->bioc));
@@ -3866,6 +3866,8 @@ static void *bg_migration_thread(void *opaque)
if (qemu_savevm_state_complete_precopy_non_iterable(fb, false, false)) {
goto fail;
}
+ qemu_fflush(fb);
What will happen if the vmstates are bigger than 512KB? Would the extra data
be dropped?