Re: [Qemu-devel] [PATCH v12 13/21] migration: Calculate transferred ram correctly

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Juan Quintela (quintela@redhat.com) wrote:
> On multifd we send data from more places that main channel.
> 
> Signed-off-by: Juan Quintela <quintela@redhat.com>
> ---
>  migration/migration.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index 9b510a809a..75d30661e9 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -2246,12 +2246,19 @@ static void migration_update_counters(MigrationState *s,
>  {
>      uint64_t transferred, time_spent;
>      double bandwidth;
> +    uint64_t now;
>  
>      if (current_time < s->iteration_start_time + BUFFER_DELAY) {
>          return;
>      }
>  
> -    transferred = qemu_ftell(s->to_dst_file) - s->iteration_initial_bytes;
> +    if (migrate_use_multifd()) {
> +        now = ram_counters.normal * qemu_target_page_size()
> +            + qemu_ftell(s->to_dst_file);

OK, can I just confirm, the 'multifd packets' go over the main fd, and
just the pags are going over the other fd's?  In which case this is
right; but if the headers are going over the other fd's as well then
this is wrong.

Dave

> +    } else {
> +        now = qemu_ftell(s->to_dst_file);
> +    }
> +    transferred = now - s->iteration_initial_bytes;
>      time_spent = current_time - s->iteration_start_time;
>      bandwidth = (double)transferred / time_spent;
>      s->threshold_size = bandwidth * s->parameters.downtime_limit;
> @@ -2271,7 +2278,7 @@ static void migration_update_counters(MigrationState *s,
>      qemu_file_reset_rate_limit(s->to_dst_file);
>  
>      s->iteration_start_time = current_time;
> -    s->iteration_initial_bytes = qemu_ftell(s->to_dst_file);
> +    s->iteration_initial_bytes = now;
>  
>      trace_migrate_transferred(transferred, time_spent,
>                                bandwidth, s->threshold_size);
> -- 
> 2.17.0
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK