Re: [Qemu-devel] [PATCH 09/11] Add migration accounting for normal and duplicate pages

[Luiz Capitulino <lcapitulino@redhat.com>]

On Sun, 29 Jul 2012 12:43:01 +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      |   38 ++++++++++++++++++++++++++++++++++++++
>  migration.c      |    4 ++++
>  migration.h      |    5 +++++
>  qapi-schema.json |    8 ++++++--
>  qmp-commands.hx  |   14 +++++++++++---
>  5 files changed, 64 insertions(+), 5 deletions(-)
> 
> diff --git a/arch_init.c b/arch_init.c
> index d709ccb..7f12317 100644
> --- a/arch_init.c
> +++ b/arch_init.c
> @@ -199,6 +199,40 @@ 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 iterations;
> +} 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;
> +}
> +
>  static void save_block_hdr(QEMUFile *f, RAMBlock *block, ram_addr_t offset,
>          int cont, int flag)
>  {
> @@ -293,6 +327,7 @@ 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;
> @@ -308,6 +343,7 @@ 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 */
> @@ -429,6 +465,7 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
>          }
>          XBZRLE.encoded_buf = g_malloc0(TARGET_PAGE_SIZE);
>          XBZRLE.current_buf = g_malloc(TARGET_PAGE_SIZE);
> +        acct_clear();
>      }
>  
>      /* Make sure all dirty bits are set */
> @@ -477,6 +514,7 @@ 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/migration.c b/migration.c
> index bc2231d..4dc99ba 100644
> --- a/migration.c
> +++ b/migration.c
> @@ -156,6 +156,8 @@ 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();
>  
>          if (blk_mig_active()) {
>              info->has_disk = true;
> @@ -175,6 +177,8 @@ MigrationInfo *qmp_query_migrate(Error **errp)
>          info->ram->remaining = 0;
>          info->ram->total = ram_bytes_total();
>          info->ram->total_time = s->total_time;
> +        info->ram->duplicate = dup_mig_pages_transferred();
> +        info->ram->normal = norm_mig_pages_transferred();
>          break;
>      case MIG_STATE_ERROR:
>          info->has_status = true;
> diff --git a/migration.h b/migration.h
> index 337e225..e4a7cd7 100644
> --- a/migration.h
> +++ b/migration.h
> @@ -87,6 +87,11 @@ 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);
> +
>  /**
>   * @migrate_add_blocker - prevent migration from proceeding
>   *
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 04adcee..a936714 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -264,11 +264,15 @@
>  #        migration has ended, it returns the total migration
>  #        time. (since 1.2)
>  #
> -# Since: 0.14.0.
> +# @duplicate: number of duplicate pages (since 1.2)
> +#
> +# @normal : number of normal pages (since 1.2)

Is the number of pages actually useful? I think this should be in bytes,
just like the other stats.

> +#
> +# Since: 0.14.0
>  ##
>  { 'type': 'MigrationStats',
>    'data': {'transferred': 'int', 'remaining': 'int', 'total': 'int' ,
> -           'total_time': 'int' } }
> +           'total_time': 'int', 'duplicate': 'int', 'normal': 'int' } }
>  
>  ##
>  # @MigrationInfo
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index cfc950e..a5a67eb 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -2099,6 +2099,8 @@ 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)
> @@ -2119,7 +2121,9 @@ Examples:
>          "ram":{
>            "transferred":123,
>            "remaining":123,
> -          "total":246
> +          "total":246,
> +          "duplicate":123,
> +          "normal":123
>          }
>       }
>     }
> @@ -2138,7 +2142,9 @@ Examples:
>           "ram":{
>              "transferred":123,
>              "remaining":123,
> -            "total":246
> +            "total":246,
> +            "duplicate":123,
> +            "normal":123
>           }
>        }
>     }
> @@ -2152,7 +2158,9 @@ Examples:
>           "ram":{
>              "total":1057024,
>              "remaining":1053304,
> -            "transferred":3720
> +            "transferred":3720,
> +            "duplicate":123,
> +            "normal":123
>           },
>           "disk":{
>              "total":20971520,