Re: [PATCH QEMU v7 8/9] migration: Extend query-migrate to provide dirty page limit info

[Markus Armbruster]

~hyman <hyman@git.sr.ht> writes:

> From: Hyman Huang(黄勇) <yong.huang@smartx.com>
>
> Extend query-migrate to provide throttle time and estimated
> ring full time with dirty-limit capability enabled, through which
> we can observe if dirty limit take effect during live migration.
>
> Signed-off-by: Hyman Huang(黄勇) <yong.huang@smartx.com>
> Reviewed-by: Markus Armbruster <armbru@redhat.com>
> Reviewed-by: Juan Quintela <quintela@redhat.com>

[...]

> diff --git a/qapi/migration.json b/qapi/migration.json
> index cc51835cdd..ebc15e2782 100644
> --- a/qapi/migration.json
> +++ b/qapi/migration.json
> @@ -250,6 +250,18 @@
>  #     blocked.  Present and non-empty when migration is blocked.
>  #     (since 6.0)
>  #
> +# @dirty-limit-throttle-time-per-round: Maximum throttle time (in 
> microseconds) of virtual
> +#                                       CPUs each dirty ring full round, 
> which shows how
> +#                                       MigrationCapability dirty-limit 
> affects the guest
> +#                                       during live migration. (since 8.1)
> +#
> +# @dirty-limit-ring-full-time: Estimated average dirty ring full time (in 
> microseconds)
> +#                              each dirty ring full round, note that the 
> value equals

Period instead of comma, please.

> +#                              dirty ring memory size divided by average 
> dirty page rate
> +#                              of virtual CPU, which can be used to observe 
> the average

of the virtual CPU

> +#                              memory load of virtual CPU indirectly. Note 
> that zero

again

> +#                              means guest doesn't dirty memory (since 8.1)
> +#

Please format like

   # @dirty-limit-throttle-time-per-round: Maximum throttle time (in
   #     microseconds) of virtual CPUs each dirty ring full round, which
   #     shows how MigrationCapability dirty-limit affects the guest
   #     during live migration.  (since 8.1)
   #
   # @dirty-limit-ring-full-time: Estimated average dirty ring full time
   #     (in microseconds) each dirty ring full round.  Note that the
   #     value equals dirty ring memory size divided by average dirty
   #     page rate of the virtual CPU, which can be used to observe the
   #     average memory load of the virtual CPU indirectly.  Note that
   #     zero means guest doesn't dirty memory (since 8.1)

to blend in with recent commit a937b6aa739 (qapi: Reformat doc comments
to conform to current conventions).

Might want to scratch "Note that" both times.

>  # Since: 0.14
>  ##
>  { 'struct': 'MigrationInfo',
> @@ -267,7 +279,9 @@
>             '*postcopy-blocktime' : 'uint32',
>             '*postcopy-vcpu-blocktime': ['uint32'],
>             '*compression': 'CompressionStats',
> -           '*socket-address': ['SocketAddress'] } }
> +           '*socket-address': ['SocketAddress'],
> +           '*dirty-limit-throttle-time-per-round': 'uint64',
> +           '*dirty-limit-ring-full-time': 'uint64'} }
>  
>  ##
>  # @query-migrate:

[...]