Re: [Qemu-devel] [PATCH 21/22] Add XBZRLE statistics

[Orit Wasserman <owasserm@redhat.com>]

On 07/23/2012 10:33 PM, Luiz Capitulino wrote:
> On Fri, 13 Jul 2012 09:23:43 +0200
> Juan Quintela <quintela@redhat.com> wrote:
> 
>> From: Orit Wasserman <owasserm@redhat.com>
>>
>> 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      |   66 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>>  hmp.c            |   13 +++++++++++
>>  migration.c      |   49 ++++++++++++++++++++++++++++++++++++++++
>>  migration.h      |    9 ++++++++
>>  qapi-schema.json |   37 +++++++++++++++++++++++++-----
>>  qmp-commands.hx  |   35 ++++++++++++++++++++++++++++-
>>  6 files changed, 203 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch_init.c b/arch_init.c
>> index d972d84..ab3fb2c 100644
>> --- a/arch_init.c
>> +++ b/arch_init.c
>> @@ -202,6 +202,64 @@ int64_t xbzrle_cache_resize(int64_t new_size)
>>      return pow2floor(new_size);
>>  }
>>
>> +/* accounting for migration statistics */
>> +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;
>> +
>> +static void acct_clear(void)
>> +{
>> +    memset(&acct_info, 0, sizeof(acct_info));
>> +}
>> +
>> +uint64_t dup_mig_bytes_transferred(void)
>> +{
>> +    return acct_info.dup_pages * TARGET_PAGE_SIZE;
>> +}
>> +
>> +uint64_t dup_mig_pages_transferred(void)
>> +{
>> +    return acct_info.dup_pages;
>> +}
>> +
>> +uint64_t norm_mig_bytes_transferred(void)
>> +{
>> +    return acct_info.norm_pages * TARGET_PAGE_SIZE;
>> +}
>> +
>> +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)
>>  {
>> @@ -230,6 +288,7 @@ 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;
>>      }
>>
>> @@ -244,6 +303,7 @@ 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;
>> @@ -263,7 +323,9 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,
>>      qemu_put_byte(f, hdr.xh_flags);
>>      qemu_put_be16(f, hdr.xh_len);
>>      qemu_put_buffer(f, XBZRLE.encoded_buf, encoded_len);
>> +    acct_info.xbzrle_pages++;
>>      bytes_sent = encoded_len + sizeof(hdr);
>> +    acct_info.xbzrle_bytes += bytes_sent;
>>
>>      return bytes_sent;
>>  }
>> @@ -303,6 +365,7 @@ static int ram_save_block(QEMUFile *f)
>>              p = memory_region_get_ram_ptr(mr) + offset;
>>
>>              if (is_dup_page(p)) {
>> +                acct_info.dup_pages++;
>>                  save_block_hdr(f, block, offset, cont, RAM_SAVE_FLAG_COMPRESS);
>>                  qemu_put_byte(f, *p);
>>                  bytes_sent = 1;
>> @@ -318,6 +381,7 @@ static int ram_save_block(QEMUFile *f)
>>                  save_block_hdr(f, block, offset, cont, RAM_SAVE_FLAG_PAGE);
>>                  qemu_put_buffer(f, p, TARGET_PAGE_SIZE);
>>                  bytes_sent = TARGET_PAGE_SIZE;
>> +                acct_info.norm_pages++;
>>              }
>>
>>              /* if page is unmodified, continue to the next */
>> @@ -437,6 +501,7 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
>>              return -1;
>>          }
>>          XBZRLE.encoded_buf = g_malloc0(TARGET_PAGE_SIZE);
>> +        acct_clear();
>>      }
>>
>>      QLIST_FOREACH(block, &ram_list.blocks, next) {
>> @@ -484,6 +549,7 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
>>              break;
>>          }
>>          bytes_transferred += bytes_sent;
>> +        acct_info.iterations++;
>>          /* we want to check in the 1st loop, just in case it was the 1st time
>>             and we had to sync the dirty bitmap.
>>             qemu_get_clock_ns() is a bit expensive, so we only check each some
>> diff --git a/hmp.c b/hmp.c
>> index 99ad00a..0d7333b 100644
>> --- a/hmp.c
>> +++ b/hmp.c
>> @@ -168,6 +168,19 @@ void hmp_info_migrate(Monitor *mon)
>>                         info->disk->total >> 10);
>>      }
>>
>> +    if (info->has_cache) {
>> +        monitor_printf(mon, "cache size: %" PRIu64 " bytes\n",
>> +                       info->cache->cache_size);
>> +        monitor_printf(mon, "xbzrle transferred: %" PRIu64 " kbytes\n",
>> +                       info->cache->xbzrle_bytes >> 10);
>> +        monitor_printf(mon, "xbzrle pages: %" PRIu64 " pages\n",
>> +                       info->cache->xbzrle_pages);
>> +        monitor_printf(mon, "xbzrle cache miss: %" PRIu64 "\n",
>> +                       info->cache->xbzrle_cache_miss);
>> +        monitor_printf(mon, "xbzrle overflow : %" PRIu64 "\n",
>> +                       info->cache->xbzrle_overflow);
>> +    }
>> +
>>      qapi_free_MigrationInfo(info);
>>  }
>>
>> diff --git a/migration.c b/migration.c
>> index d134bf6..e11f451 100644
>> --- a/migration.c
>> +++ b/migration.c
>> @@ -137,6 +137,17 @@ MigrationInfo *qmp_query_migrate(Error **errp)
>>              info->capabilities->value->state = s->enabled_capabilities[i];
>>              info->capabilities->next = NULL;
>>          }
>> +
>> +        /* display xbzrle cache size */
>> +        if (migrate_use_xbzrle()) {
>> +            info->has_cache = true;
>> +            info->cache = g_malloc0(sizeof(*info->cache));
>> +            info->cache->cache_size = migrate_xbzrle_cache_size();
>> +            info->cache->xbzrle_bytes = xbzrle_mig_bytes_transferred();
>> +            info->cache->xbzrle_pages = xbzrle_mig_pages_transferred();
>> +            info->cache->xbzrle_cache_miss = xbzrle_mig_pages_cache_miss();
>> +            info->cache->xbzrle_overflow = xbzrle_mig_pages_overflow();
>> +        }
> 
> Why do you need this in MIG_STATE_SETUP? I think having it only in
> MIG_STATE_ACTIVE is enough (and probably that's what we want).
you are right we just need the cache size (which can be set before the migration).
> 
>>          break;
>>      case MIG_STATE_ACTIVE:
>>          for (i = 0; i < MIGRATION_CAPABILITY_MAX; i++) {
>> @@ -161,6 +172,8 @@ MigrationInfo *qmp_query_migrate(Error **errp)
>>          info->ram->total = ram_bytes_total();
>>          info->ram->total_time = qemu_get_clock_ms(rt_clock)
>>              - s->total_time;
>> +        info->ram->duplicate = dup_mig_pages_transferred();
>> +        info->ram->normal = norm_mig_pages_transferred();
> 
> Can we do this extension in a different patch?
ok
> 
>>
>>          if (blk_mig_active()) {
>>              info->has_disk = true;
>> @@ -169,6 +182,16 @@ MigrationInfo *qmp_query_migrate(Error **errp)
>>              info->disk->remaining = blk_mig_bytes_remaining();
>>              info->disk->total = blk_mig_bytes_total();
>>          }
>> +
>> +        if (migrate_use_xbzrle()) {
>> +            info->has_cache = true;
>> +            info->cache = g_malloc0(sizeof(*info->cache));
>> +            info->cache->cache_size = migrate_xbzrle_cache_size();
>> +            info->cache->xbzrle_bytes = xbzrle_mig_bytes_transferred();
>> +            info->cache->xbzrle_pages = xbzrle_mig_pages_transferred();
>> +            info->cache->xbzrle_cache_miss = xbzrle_mig_pages_cache_miss();
>> +            info->cache->xbzrle_overflow = xbzrle_mig_pages_overflow();
>> +        }
>>          break;
>>      case MIG_STATE_COMPLETED:
>>          for (i = 0; i < MIGRATION_CAPABILITY_MAX; i++) {
>> @@ -183,6 +206,32 @@ MigrationInfo *qmp_query_migrate(Error **errp)
>>              info->capabilities->next = NULL;
>>          }
>>
>> +        info->has_ram = true;
>> +        info->ram = g_malloc0(sizeof(*info->ram));
>> +        info->ram->transferred = ram_bytes_transferred();
>> +        info->ram->remaining = ram_bytes_remaining();
>> +        info->ram->total = ram_bytes_total();
>> +        info->ram->duplicate = dup_mig_pages_transferred();
>> +        info->ram->normal = norm_mig_pages_transferred();
> 
> This hunk is probably bad copy & paste, as this code already exists.
looks like a bad merge I will remove it
> 
>> +
>> +        if (blk_mig_active()) {
>> +            info->has_disk = true;
>> +            info->disk = g_malloc0(sizeof(*info->disk));
>> +            info->disk->transferred = blk_mig_bytes_transferred();
>> +            info->disk->remaining = blk_mig_bytes_remaining();
>> +            info->disk->total = blk_mig_bytes_total();
>> +        }
> 
> Why are you doing this, bad copy & paste too?
looks like a bad merge I will remove it
> 
>> +
>> +        if (migrate_use_xbzrle()) {
>> +            info->has_cache = true;
>> +            info->cache = g_malloc0(sizeof(*info->cache));
>> +            info->cache->cache_size = migrate_xbzrle_cache_size();
>> +            info->cache->xbzrle_bytes = xbzrle_mig_bytes_transferred();
>> +            info->cache->xbzrle_pages = xbzrle_mig_pages_transferred();
>> +            info->cache->xbzrle_cache_miss = xbzrle_mig_pages_cache_miss();
>> +            info->cache->xbzrle_overflow = xbzrle_mig_pages_overflow();
>> +        }
>> +
>>          info->has_status = true;
>>          info->status = g_strdup("completed");
>>
>> diff --git a/migration.h b/migration.h
>> index 337e225..a9852fc 100644
>> --- a/migration.h
>> +++ b/migration.h
>> @@ -87,6 +87,15 @@ uint64_t ram_bytes_total(void);
>>
>>  extern SaveVMHandlers savevm_ram_handlers;
>>
>> +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 a0f0f95..961810b 100644
>> --- a/qapi-schema.json
>> +++ b/qapi-schema.json
>> @@ -264,11 +264,35 @@
>>  #        migration has ended, it returns the total migration
>>  #        time. (since 1.2)
>>  #
>> -# Since: 0.14.0.
>> +# @duplicate: #optional, number of duplicate pages
>> +#
>> +# @normal : #optional, number of normal pages
>> +#
>> +# Since: 0.14.0, 'duplicate' and 'normal' since 1.2
> 
> Please, put 'since' in the same line of the field, like this:
> 
>  @normal : #optional, number of normal pages (since 1.2)
ok
> 
>>  ##
>>  { 'type': 'MigrationStats',
>>    'data': {'transferred': 'int', 'remaining': 'int', 'total': 'int' ,
>> -           'total_time': 'int' } }
>> +           'total_time': 'int', '*duplicate': 'int', '*normal': 'int' } }
>> +##
>> +# @CacheStats
> 
> This is specific to xbzrle, right? So this should be called XBZRLECacheStats,
> or something.
sure
> 
>> +#
>> +# Detailed XBZRLE migration cache statistics
>> +#
>> +# @cache_size: XBZRLE cache size
>> +#
>> +# @xbzrle_bytes: amount of bytes already transferred to the target VM
>> +#
>> +# @xbzrle_pages: amount of pages transferred to the target VM
>> +#
>> +# @xbzrle_cache_miss: number of cache miss
>> +#
>> +# @xbzrle_overflow: number of overflows
>> +#
>> +# Since: 1.2
>> +##
>> +{ 'type': 'CacheStats',
>> +  'data': {'cache-size': 'int', 'xbzrle-bytes': 'int', 'xbzrle-pages': 'int',
>> +           'xbzrle-cache-miss': 'int', 'xbzrle-overflow': 'int' } }
>>
>>  ##
>>  # @MigrationInfo
>> @@ -291,13 +315,16 @@
>>  # @capabilities: #optional a list describing all the migration capabilities
>>  #                state
>>  #
>> -# Since: 0.14.0, 'capabilities' since 1.2
>> +# @cache: #optional @MigrationStats containing detailed XBZRLE migration
>> +#         statistics
> 
> xbzrle-cache.
ok

Thanks,
Orit
> 
>> +#
>> +# Since: 0.14.0, 'capabilities' and 'cache' since 1.2
>>  ##
>>  { 'type': 'MigrationInfo',
>>    'data': {'*status': 'str', '*ram': 'MigrationStats',
>>             '*disk': 'MigrationStats',
>> -           '*capabilities': ['MigrationCapabilityInfo']} }
>> -
>> +           '*capabilities': ['MigrationCapabilityInfo'],
>> +           '*cache': 'CacheStats'} }
>>  ##
>>  # @query-migrate
>>  #
>> diff --git a/qmp-commands.hx b/qmp-commands.hx
>> index a3d57ce..34d4675 100644
>> --- a/qmp-commands.hx
>> +++ b/qmp-commands.hx
>> @@ -2093,6 +2093,8 @@ The main json-object contains the following:
>>           - "transferred": amount transferred (json-int)
>>           - "remaining": amount remaining (json-int)
>>           - "total": total (json-int)
>> +	 - "duplicate": number of duplicated pages (json-int)
>> +	 - "normal" : number of normal pages transferred (json-int)
>>  - "disk": only present if "status" is "active" and it is a block migration,
>>    it is a json-object with the following disk information (in bytes):
>>           - "transferred": amount transferred (json-int)
>> @@ -2100,10 +2102,17 @@ The main json-object contains the following:
>>           - "total": total (json-int)
>>  - "capabilities": migration capabilities state
>>           - "xbzrle" : XBZRLE state (json-bool)
>> +- "cache": only present if "status" and XBZRLE is active.
>> +  It is a json-object with the following XBZRLE information:
>> +         - "cache-size": XBZRLE cache size
>> +         - "xbzrle-bytes": total XBZRLE bytes transferred
>> +         - "xbzrle-pages": number of XBZRLE compressed pages
>> +         - "cache-miss": number of cache misses
>> +         - "overflow": number of XBZRLE overflows
>> +
>>  Examples:
>>
>>  1. Before the first migration
>> -
>>  -> { "execute": "query-migrate" }
>>  <- { "return": {
>>          "capabilities" :  [ { "capability" : "xbzrle", "state" : false } ]
>> @@ -2164,6 +2173,30 @@ 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
>>
>>      {
>