Re: [Qemu-devel] [PATCH v2 3/5] Postcopy: Add stats on page requests

["Denis V. Lunev" <den@openvz.org>]

On 04/29/2016 05:47 PM, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
>
> On the source, add a count of page requests received from the
> destination.
>
> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> ---
>   hmp.c                         | 4 ++++
>   include/migration/migration.h | 2 ++
>   migration/migration.c         | 2 ++
>   migration/ram.c               | 1 +
>   qapi-schema.json              | 6 +++++-
>   5 files changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/hmp.c b/hmp.c
> index d510236..cd5fae3 100644
> --- a/hmp.c
> +++ b/hmp.c
> @@ -209,6 +209,10 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
>               monitor_printf(mon, "dirty pages rate: %" PRIu64 " pages\n",
>                              info->ram->dirty_pages_rate);
>           }
> +        if (info->ram->postcopy_requests) {
> +            monitor_printf(mon, "postcopy request count: %" PRIu64 "\n",
> +                           info->ram->postcopy_requests);
> +        }
>       }
>   
>       if (info->has_disk) {
> diff --git a/include/migration/migration.h b/include/migration/migration.h
> index ac2c12c..78fa59b 100644
> --- a/include/migration/migration.h
> +++ b/include/migration/migration.h
> @@ -157,6 +157,8 @@ struct MigrationState
>       int64_t xbzrle_cache_size;
>       int64_t setup_time;
>       int64_t dirty_sync_count;
> +    /* Count of requests incoming from destination */
> +    int64_t postcopy_requests;
>   
>       /* Flag set once the migration has been asked to enter postcopy */
>       bool start_postcopy;
> diff --git a/migration/migration.c b/migration/migration.c
> index bfb326d..9d41618 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -573,6 +573,7 @@ static void populate_ram_info(MigrationInfo *info, MigrationState *s)
>       info->ram->normal_bytes = norm_mig_bytes_transferred();
>       info->ram->mbps = s->mbps;
>       info->ram->dirty_sync_count = s->dirty_sync_count;
> +    info->ram->postcopy_requests = s->postcopy_requests;
>   
>       if (s->state != MIGRATION_STATUS_COMPLETED) {
>           info->ram->remaining = ram_bytes_remaining();
> @@ -933,6 +934,7 @@ MigrationState *migrate_init(const MigrationParams *params)
>       s->dirty_sync_count = 0;
>       s->start_postcopy = false;
>       s->postcopy_after_devices = false;
> +    s->postcopy_requests = 0;
>       s->migration_thread_running = false;
>       s->last_req_rb = NULL;
>   
> diff --git a/migration/ram.c b/migration/ram.c
> index e96c2af..eeb1902 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -1169,6 +1169,7 @@ int ram_save_queue_pages(MigrationState *ms, const char *rbname,
>   {
>       RAMBlock *ramblock;
>   
> +    ms->postcopy_requests++;
>       rcu_read_lock();
>       if (!rbname) {
>           /* Reuse last RAMBlock */
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 54634c4..8bc581e 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -382,13 +382,17 @@
>   #
>   # @dirty-sync-count: number of times that dirty ram was synchronized (since 2.1)
>   #
> +# @postcopy-requests: The number of page requests received from the destination
> +#        (since 2.7)
> +#
>   # Since: 0.14.0
>   ##
>   { 'struct': 'MigrationStats',
>     'data': {'transferred': 'int', 'remaining': 'int', 'total': 'int' ,
>              'duplicate': 'int', 'skipped': 'int', 'normal': 'int',
>              'normal-bytes': 'int', 'dirty-pages-rate' : 'int',
> -           'mbps' : 'number', 'dirty-sync-count' : 'int' } }
> +           'mbps' : 'number', 'dirty-sync-count' : 'int',
> +           'postcopy-requests' : 'int' } }
>   
>   ##
>   # @XBZRLECacheStats
Reviewed-by: Denis V. Lunev <den@openvz.org>