Re: [Qemu-devel] [RFC PATCH v5 2/3] Add 'auto-converge' migration capability

[Paolo Bonzini <pbonzini@redhat.com>]

Il 09/05/2013 21:43, Chegu Vinod ha scritto:
>  The auto-converge migration capability allows the user to specify if they
>  choose live migration seqeunce to automatically detect and force convergence.
> 
> Signed-off-by: Chegu Vinod <chegu_vinod@hp.com>
> ---
>  include/migration/migration.h |    2 ++
>  migration.c                   |    9 +++++++++
>  qapi-schema.json              |    5 ++++-
>  3 files changed, 15 insertions(+), 1 deletions(-)
> 
> diff --git a/include/migration/migration.h b/include/migration/migration.h
> index e2acec6..ace91b0 100644
> --- a/include/migration/migration.h
> +++ b/include/migration/migration.h
> @@ -127,4 +127,6 @@ int migrate_use_xbzrle(void);
>  int64_t migrate_xbzrle_cache_size(void);
>  
>  int64_t xbzrle_cache_resize(int64_t new_size);
> +
> +bool migrate_auto_converge(void);
>  #endif
> diff --git a/migration.c b/migration.c
> index 3eb0fad..570cee5 100644
> --- a/migration.c
> +++ b/migration.c
> @@ -474,6 +474,15 @@ void qmp_migrate_set_downtime(double value, Error **errp)
>      max_downtime = (uint64_t)value;
>  }
>  
> +bool migrate_auto_converge(void)
> +{
> +    MigrationState *s;
> +
> +    s = migrate_get_current();
> +
> +    return s->enabled_capabilities[MIGRATION_CAPABILITY_AUTO_CONVERGE];
> +}
> +
>  int migrate_use_xbzrle(void)
>  {
>      MigrationState *s;
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 199744a..b33839c 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -602,10 +602,13 @@
>  #          This feature allows us to minimize migration traffic for certain work
>  #          loads, by sending compressed difference of the pages
>  #
> +# @auto-converge: Migration supports automatic throttling down of guest
> +#          to force convergence. (since 1.6)

If enabled, QEMU will automatically throttle down the guest to speed up
convergence of RAM migration.

> +#
>  # Since: 1.2
>  ##
>  { 'enum': 'MigrationCapability',
> -  'data': ['xbzrle'] }
> +  'data': ['xbzrle', 'auto-converge'] }
>  
>  ##
>  # @MigrationCapabilityStatus
> 

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>