Re: [Qemu-devel] [PATCH 10/11] Add XBZRLE statistics

[Luiz Capitulino <lcapitulino@redhat.com>]

On Sun, 29 Jul 2012 12:43:02 +0300
Orit Wasserman <owasserm@redhat.com> wrote:

> Signed-off-by: Benoit Hudzia <benoit.hudzia@sap.com>
> Signed-off-by: Petter Svard <petters@cs.umu.se>
> Signed-off-by: Aidan Shribman <aidan.shribman@sap.com>
> Signed-off-by: Orit Wasserman <owasserm@redhat.com>
> Signed-off-by: Juan Quintela <quintela@redhat.com>
> ---
>  arch_init.c      |   28 ++++++++++++++++++++++++++++
>  hmp.c            |   21 +++++++++++++++++++++
>  migration.c      |   28 ++++++++++++++++++++++++++++
>  migration.h      |    4 ++++
>  qapi-schema.json |   32 +++++++++++++++++++++++++++++++-
>  qmp-commands.hx  |   35 +++++++++++++++++++++++++++++++++++
>  6 files changed, 147 insertions(+), 1 deletions(-)
> 
> diff --git a/arch_init.c b/arch_init.c
> index 7f12317..9833d54 100644
> --- a/arch_init.c
> +++ b/arch_init.c
> @@ -203,7 +203,11 @@ int64_t xbzrle_cache_resize(int64_t new_size)
>  typedef struct AccountingInfo {
>      uint64_t dup_pages;
>      uint64_t norm_pages;
> +    uint64_t xbzrle_bytes;
> +    uint64_t xbzrle_pages;
> +    uint64_t xbzrle_cache_miss;
>      uint64_t iterations;
> +    uint64_t xbzrle_overflows;
>  } AccountingInfo;
>  
>  static AccountingInfo acct_info;
> @@ -233,6 +237,26 @@ uint64_t norm_mig_pages_transferred(void)
>      return acct_info.norm_pages;
>  }
>  
> +uint64_t xbzrle_mig_bytes_transferred(void)
> +{
> +    return acct_info.xbzrle_bytes;
> +}
> +
> +uint64_t xbzrle_mig_pages_transferred(void)
> +{
> +    return acct_info.xbzrle_pages;
> +}
> +
> +uint64_t xbzrle_mig_pages_cache_miss(void)
> +{
> +    return acct_info.xbzrle_cache_miss;
> +}
> +
> +uint64_t xbzrle_mig_pages_overflow(void)
> +{
> +    return acct_info.xbzrle_overflows;
> +}
> +
>  static void save_block_hdr(QEMUFile *f, RAMBlock *block, ram_addr_t offset,
>          int cont, int flag)
>  {
> @@ -257,6 +281,7 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,
>      if (!cache_is_cached(XBZRLE.cache, current_addr)) {
>          cache_insert(XBZRLE.cache, current_addr,
>                       g_memdup(current_data, TARGET_PAGE_SIZE));
> +        acct_info.xbzrle_cache_miss++;
>          return -1;
>      }
>  
> @@ -274,6 +299,7 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,
>          return 0;
>      } else if (encoded_len == -1) {
>          DPRINTF("Overflow\n");
> +        acct_info.xbzrle_overflows++;
>          /* update data in the cache */
>          memcpy(prev_cached_page, current_data, TARGET_PAGE_SIZE);
>          return -1;
> @@ -288,6 +314,8 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,
>      qemu_put_be16(f, encoded_len);
>      qemu_put_buffer(f, XBZRLE.encoded_buf, encoded_len);
>      bytes_sent = encoded_len + 1 + 2;
> +    acct_info.xbzrle_pages++;
> +    acct_info.xbzrle_bytes += bytes_sent;
>  
>      return bytes_sent;
>  }
> diff --git a/hmp.c b/hmp.c
> index 9770d7b..383d5b1 100644
> --- a/hmp.c
> +++ b/hmp.c
> @@ -172,6 +172,27 @@ void hmp_info_migrate(Monitor *mon)
>                         info->disk->total >> 10);
>      }
>  
> +    if (info->has_xbzrle_cache) {
> +        monitor_printf(mon, "cache size: %" PRIu64 " bytes\n",
> +                       info->xbzrle_cache->cache_size);
> +        if (info->xbzrle_cache->has_xbzrle_bytes) {
> +            monitor_printf(mon, "xbzrle transferred: %" PRIu64 " kbytes\n",
> +                           info->xbzrle_cache->xbzrle_bytes >> 10);
> +        }
> +        if (info->xbzrle_cache->has_xbzrle_pages) {
> +            monitor_printf(mon, "xbzrle pages: %" PRIu64 " pages\n",
> +                           info->xbzrle_cache->xbzrle_pages);
> +        }
> +        if (info->xbzrle_cache->has_xbzrle_cache_miss) {
> +            monitor_printf(mon, "xbzrle cache miss: %" PRIu64 "\n",
> +                           info->xbzrle_cache->xbzrle_cache_miss);
> +        }
> +        if (info->xbzrle_cache->has_xbzrle_overflow) {
> +            monitor_printf(mon, "xbzrle overflow : %" PRIu64 "\n",
> +                           info->xbzrle_cache->xbzrle_overflow);
> +        }
> +    }
> +
>      qapi_free_MigrationInfo(info);
>      qapi_free_MigrationParameters(params);
>  }
> diff --git a/migration.c b/migration.c
> index 4dc99ba..fb802bc 100644
> --- a/migration.c
> +++ b/migration.c
> @@ -136,6 +136,23 @@ MigrationParameters *qmp_query_migrate_parameters(Error **errp)
>      return params;
>  }
>  
> +static void get_xbzrle_cache_stats(MigrationInfo *info)
> +{
> +    if (migrate_use_xbzrle()) {
> +        info->has_xbzrle_cache = true;
> +        info->xbzrle_cache = g_malloc0(sizeof(*info->xbzrle_cache));
> +        info->xbzrle_cache->cache_size = migrate_xbzrle_cache_size();
> +        info->xbzrle_cache->has_xbzrle_bytes = true;
> +        info->xbzrle_cache->xbzrle_bytes = xbzrle_mig_bytes_transferred();
> +        info->xbzrle_cache->has_xbzrle_pages = true;
> +        info->xbzrle_cache->xbzrle_pages = xbzrle_mig_pages_transferred();
> +        info->xbzrle_cache->has_xbzrle_cache_miss = true;
> +        info->xbzrle_cache->xbzrle_cache_miss = xbzrle_mig_pages_cache_miss();
> +        info->xbzrle_cache->has_xbzrle_overflow = true;
> +        info->xbzrle_cache->xbzrle_overflow = xbzrle_mig_pages_overflow();
> +    }
> +}
> +
>  MigrationInfo *qmp_query_migrate(Error **errp)
>  {
>      MigrationInfo *info = g_malloc0(sizeof(*info));
> @@ -144,6 +161,13 @@ MigrationInfo *qmp_query_migrate(Error **errp)
>      switch (s->state) {
>      case MIG_STATE_SETUP:
>          /* no migration has happened ever */
> +
> +        /* display xbzrle cache size */
> +        if (migrate_use_xbzrle()) {
> +            info->has_xbzrle_cache = true;
> +            info->xbzrle_cache = g_malloc0(sizeof(*info->xbzrle_cache));
> +            info->xbzrle_cache->cache_size = migrate_xbzrle_cache_size();
> +        }

Is it really useful to return this in MIG_SETUP? Can't the cache size
be queried by some query- command?

>          break;
>      case MIG_STATE_ACTIVE:
>          info->has_status = true;
> @@ -166,8 +190,12 @@ MigrationInfo *qmp_query_migrate(Error **errp)
>              info->disk->remaining = blk_mig_bytes_remaining();
>              info->disk->total = blk_mig_bytes_total();
>          }
> +
> +        get_xbzrle_cache_stats(info);
>          break;
>      case MIG_STATE_COMPLETED:
> +        get_xbzrle_cache_stats(info);
> +
>          info->has_status = true;
>          info->status = g_strdup("completed");
>  
> diff --git a/migration.h b/migration.h
> index e4a7cd7..a9852fc 100644
> --- a/migration.h
> +++ b/migration.h
> @@ -91,6 +91,10 @@ uint64_t dup_mig_bytes_transferred(void);
>  uint64_t dup_mig_pages_transferred(void);
>  uint64_t norm_mig_bytes_transferred(void);
>  uint64_t norm_mig_pages_transferred(void);
> +uint64_t xbzrle_mig_bytes_transferred(void);
> +uint64_t xbzrle_mig_pages_transferred(void);
> +uint64_t xbzrle_mig_pages_overflow(void);
> +uint64_t xbzrle_mig_pages_cache_miss(void);
>  
>  /**
>   * @migrate_add_blocker - prevent migration from proceeding
> diff --git a/qapi-schema.json b/qapi-schema.json
> index a936714..91dee72 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -275,6 +275,31 @@
>             'total_time': 'int', 'duplicate': 'int', 'normal': 'int' } }
>  
>  ##
> +# @XBZRLECacheStats
> +#
> +# Detailed XBZRLE migration cache statistics
> +#
> +# @cache-size: XBZRLE cache size
> +#
> +# @xbzrle-bytes: @optional, amount of bytes already transferred to the target VM
> +#                only returned when migration is active or completed

s/xbzrle-bytes/transferred-bytes

> +#
> +# @xbzrle-pages: @optional, amount of pages transferred to the target VM
> +#                only returned when migration is active or completed

s/xbzrle-pages/transferred-pages

> +#
> +# @xbzrle-cache-miss: @optional, number of cache miss
> +#                     only returned when migration is active or completed

s/xbzrle/xbzrle//

> +#
> +# @xbzrle-overflow: @optional, number of overflows
> +#                   only returned when migration is active or completed

s/xbzrle///

Besides, all these parameters shouldn't be optional as they are unconditionally
included (BZRLECacheStats itself is optional as returned by query-migrate).

> +#
> +# Since: 1.2
> +##
> +{ 'type': 'XBZRLECacheStats',
> +  'data': {'cache-size': 'int', '*xbzrle-bytes': 'int', '*xbzrle-pages': 'int',
> +           '*xbzrle-cache-miss': 'int', '*xbzrle-overflow': 'int' } }
> +
> +##
>  # @MigrationInfo
>  #
>  # Information about current migration process.
> @@ -292,11 +317,16 @@
>  #        status, only returned if status is 'active' and it is a block
>  #        migration
>  #
> +# @xbzrle-cache: #optional @XBZRLECacheStats containing detailed XBZRLE
> +#                migration statistics, only returned if XBZRLE feature is on
> +#                (since 1.2)
> +#
>  # Since: 0.14.0
>  ##
>  { 'type': 'MigrationInfo',
>    'data': {'*status': 'str', '*ram': 'MigrationStats',
> -           '*disk': 'MigrationStats'} }
> +           '*disk': 'MigrationStats',
> +           '*xbzrle-cache': 'XBZRLECacheStats'} }
>  
>  ##
>  # @query-migrate
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index a5a67eb..0546f42 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -2106,6 +2106,17 @@ The main json-object contains the following:
>           - "transferred": amount transferred (json-int)
>           - "remaining": amount remaining (json-int)
>           - "total": total (json-int)
> +- "xbzrle-cache": only present if XBZRLE is active.
> +  It is a json-object with the following XBZRLE information:
> +         - "cache-size": XBZRLE cache size
> +         - "xbzrle-bytes": total XBZRLE bytes transferred, only present if
> +                           status is "active" or "completed"
> +         - "xbzrle-pages": number of XBZRLE compressed pages, only present if
> +                           status is "active" or "completed"
> +         - "cache-miss": number of cache misses, only present if
> +                           status is "active" or "completed"
> +         - "overflow": number of XBZRLE overflows, only present if
> +                           status is "active" or "completed"
>  Examples:
>  
>  1. Before the first migration
> @@ -2170,6 +2181,30 @@ Examples:
>        }
>     }
>  
> +6. Migration is being performed and XBZRLE is active:
> +
> +-> { "execute": "query-migrate" }
> +<- {
> +      "return":{
> +         "status":"active",
> +         "capabilities" : [ { "capability": "xbzrle", "state" : true } ],
> +         "ram":{
> +            "total":1057024,
> +            "remaining":1053304,
> +            "transferred":3720,
> +            "duplicate": 10,
> +            "normal" : 3333
> +         },
> +         "cache":{
> +            "cache-size": 1024
> +            "xbzrle-transferred":20971520,
> +            "xbzrle-pages":2444343,
> +            "xbzrle-cache-miss":2244,
> +            "xbzrle-overflow":34434
> +         }
> +      }
> +   }
> +
>  EQMP
>  
>      {