Re: [Qemu-devel] [PATCH 09/11] migration: cleanup stats update into function

[Juan Quintela <quintela@redhat.com>]

Peter Xu <peterx@redhat.com> wrote:
> We have quite a few lines in migration_thread() that calculates some
> statistics for the migration interations.  Isolate it into a single
> function to improve readability.
>
> Signed-off-by: Peter Xu <peterx@redhat.com>



> +static void migration_update_statistics(MigrationState *s,


migration_update_counters()?

statistics for me mean that they are only used for informative
purposes.  Here we *act* on that values.


>  
> -            qemu_file_reset_rate_limit(s->to_dst_file);
> -            initial_time = current_time;
> -            initial_bytes = qemu_ftell(s->to_dst_file);
> -        }
> +        /* Conditionally update statistics */

No need for the comment.  If we think it is needed just rename the
function to:
   conditionally_update_statistics()?

I still preffer the:
   migration_update_counters.


> diff --git a/migration/migration.h b/migration/migration.h
> index 3ab5506233..248f7d9a5c 100644
> --- a/migration/migration.h
> +++ b/migration/migration.h
> @@ -90,6 +90,19 @@ struct MigrationState
>      QEMUBH *cleanup_bh;
>      QEMUFile *to_dst_file;
>  
> +    /*
> +     * Migration thread statistic variables, mostly used in
> +     * migration_thread() iterations only.
> +     */
> +    uint64_t initial_bytes;

       /* bytes already send at the beggining of current interation */
       uint64_t iteration_initial_bytes;

> +    int64_t initial_time;
       /* time at the start of current iteration */
       int64_t iteration_start_time;

What do you think?

> +    /*
> +     * The final stage happens when the remaining data is smaller than
> +     * this threshold; it's calculated from the requested downtime and
> +     * measured bandwidth
> +     */
> +    int64_t threshold_size;
> +
>      /* params from 'migrate-set-parameters' */
>      MigrationParameters parameters;

Later, Juan.