"Dr. David Alan Gilbert (git)" <dgilb...@redhat.com> writes:
> From: Yury Kotov <yury-ko...@yandex-team.ru>
>
> We want to use local migration to update QEMU for running guests.
> In this case we don't need to migrate shared (file backed) RAM.
> So, add a capability to ignore such blocks during live migration.
>
> Signed-off-by: Yury Kotov <yury-ko...@yandex-team.ru>
> Message-Id: <20190215174548.2630-3-yury-ko...@yandex-team.ru>
> Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> ---
[...]
> diff --git a/qapi/migration.json b/qapi/migration.json
> index 1fd7bbea9b..eab87340b2 100644
> --- a/qapi/migration.json
> +++ b/qapi/migration.json
> @@ -409,13 +409,16 @@
> # devices (and thus take locks) immediately at the end of
> migration.
> # (since 3.0)
> #
> +# @x-ignore-shared: If enabled, QEMU will not migrate shared memory (since
> 4.0)
What exactly is considered "shared memory"?
Specifically: say you have an ivshmem-plain device. Is its shared
memory migrated?
No objection to the pull request; if documentation improvements are
necessary, we can do them in a follow-up patch.
> +#
> # Since: 1.2
> ##
> { 'enum': 'MigrationCapability',
> 'data': ['xbzrle', 'rdma-pin-all', 'auto-converge', 'zero-blocks',
> 'compress', 'events', 'postcopy-ram', 'x-colo', 'release-ram',
> 'block', 'return-path', 'pause-before-switchover', 'x-multifd',
> - 'dirty-bitmaps', 'postcopy-blocktime', 'late-block-activate' ] }
> + 'dirty-bitmaps', 'postcopy-blocktime', 'late-block-activate',
> + 'x-ignore-shared' ] }
>
> ##
> # @MigrationCapabilityStatus:
