| Message ID | 20210401092226.102804-2-andrey.gruzdev@virtuozzo.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | migration: Fixes to the 'background-snapshot' code | expand |
* Andrey Gruzdev (andrey.gruzdev@virtuozzo.com) 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. > > Fixes: 8518278a6af589ccc401f06e35f171b1e6fae800 (migration: implementation > of background snapshot thread) > Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > --- > migration/migration.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/migration/migration.c b/migration/migration.c > index ca8b97baa5..00e13f9d58 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 +3866,12 @@ static void *bg_migration_thread(void *opaque) > if (qemu_savevm_state_complete_precopy_non_iterable(fb, false, false)) { > goto fail; > } > + /* > + * Since we are going to get non-iterable state data directly > + * from s->bioc->data, explicit flush is needed here. > + */ > + qemu_fflush(fb); > + > /* Now initialize UFFD context and start tracking RAM writes */ > if (ram_write_tracking_start()) { > goto fail; > -- > 2.27.0 > >
* Andrey Gruzdev (andrey.gruzdev@virtuozzo.com) 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. > > Fixes: 8518278a6af589ccc401f06e35f171b1e6fae800 (migration: implementation > of background snapshot thread) > Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> OK, but in future, please keep separate things separate - the buffer size increase in particular. > --- > migration/migration.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/migration/migration.c b/migration/migration.c > index ca8b97baa5..00e13f9d58 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 +3866,12 @@ static void *bg_migration_thread(void *opaque) > if (qemu_savevm_state_complete_precopy_non_iterable(fb, false, false)) { > goto fail; > } > + /* > + * Since we are going to get non-iterable state data directly > + * from s->bioc->data, explicit flush is needed here. > + */ > + qemu_fflush(fb); > + > /* Now initialize UFFD context and start tracking RAM writes */ > if (ram_write_tracking_start()) { > goto fail; > -- > 2.27.0 > >
On 06.04.2021 15:29, Dr. David Alan Gilbert wrote: > * Andrey Gruzdev (andrey.gruzdev@virtuozzo.com) 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. >> >> Fixes: 8518278a6af589ccc401f06e35f171b1e6fae800 (migration: implementation >> of background snapshot thread) >> Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com> > Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > > OK, but in future, please keep separate things separate - the buffer > size increase in particular. Got it, thanks. >> --- >> migration/migration.c | 8 +++++++- >> 1 file changed, 7 insertions(+), 1 deletion(-) >> >> diff --git a/migration/migration.c b/migration/migration.c >> index ca8b97baa5..00e13f9d58 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 +3866,12 @@ static void *bg_migration_thread(void *opaque) >> if (qemu_savevm_state_complete_precopy_non_iterable(fb, false, false)) { >> goto fail; >> } >> + /* >> + * Since we are going to get non-iterable state data directly >> + * from s->bioc->data, explicit flush is needed here. >> + */ >> + qemu_fflush(fb); >> + >> /* Now initialize UFFD context and start tracking RAM writes */ >> if (ram_write_tracking_start()) { >> goto fail; >> -- >> 2.27.0 >> >>
diff --git a/migration/migration.c b/migration/migration.c index ca8b97baa5..00e13f9d58 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 +3866,12 @@ static void *bg_migration_thread(void *opaque) if (qemu_savevm_state_complete_precopy_non_iterable(fb, false, false)) { goto fail; } + /* + * Since we are going to get non-iterable state data directly + * from s->bioc->data, explicit flush is needed here. + */ + qemu_fflush(fb); + /* Now initialize UFFD context and start tracking RAM writes */ if (ram_write_tracking_start()) { goto fail;
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. Fixes: 8518278a6af589ccc401f06e35f171b1e6fae800 (migration: implementation of background snapshot thread) Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com> --- migration/migration.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)