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| author | Hyman Huang(黄勇) <yong.huang@smartx.com> | 2023-06-07 23:30:50 +0800 |
|---|---|---|
| committer | Juan Quintela <quintela@redhat.com> | 2023-07-26 10:55:56 +0200 |
| commit | dc62395557b29312a9c2f9a1e0beece2557c3078 (patch) | |
| tree | 46c5d5bb78b2371af4825676d451b74af3abeb6e /qapi | |
| parent | 09f9ec99133ab5735b57486323d9c592630c9fc1 (diff) | |
| download | qemu-dc62395557b29312a9c2f9a1e0beece2557c3078.zip qemu-dc62395557b29312a9c2f9a1e0beece2557c3078.tar.gz qemu-dc62395557b29312a9c2f9a1e0beece2557c3078.tar.bz2 | |
migration: Introduce dirty-limit capability
Introduce migration dirty-limit capability, which can
be turned on before live migration and limit dirty
page rate durty live migration.
Introduce migrate_dirty_limit function to help check
if dirty-limit capability enabled during live migration.
Meanwhile, refactor vcpu_dirty_rate_stat_collect
so that period can be configured instead of hardcoded.
dirty-limit capability is kind of like auto-converge
but using dirty limit instead of traditional cpu-throttle
to throttle guest down. To enable this feature, turn on
the dirty-limit capability before live migration using
migrate-set-capabilities, and set the parameters
"x-vcpu-dirty-limit-period", "vcpu-dirty-limit" suitably
to speed up convergence.
Signed-off-by: Hyman Huang(黄勇) <yong.huang@smartx.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <168618975839.6361.17407633874747688653-4@git.sr.ht>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Diffstat (limited to 'qapi')
| -rw-r--r-- | qapi/migration.json | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/qapi/migration.json b/qapi/migration.json index 22104ce..e094438 100644 --- a/qapi/migration.json +++ b/qapi/migration.json @@ -497,6 +497,16 @@ # are present. 'return-path' capability must be enabled to use # it. (since 8.1) # +# @dirty-limit: If enabled, migration will use the dirty-limit algo to +# throttle down guest instead of auto-converge algo. +# Throttle algo only works when vCPU's dirtyrate greater +# than 'vcpu-dirty-limit', read processes in guest os +# aren't penalized any more, so this algo can improve +# performance of vCPU during live migration. This is an +# optional performance feature and should not affect the +# correctness of the existing auto-converge algo. +# (since 8.1) +# # Features: # # @unstable: Members @x-colo and @x-ignore-shared are experimental. @@ -512,7 +522,8 @@ 'dirty-bitmaps', 'postcopy-blocktime', 'late-block-activate', { 'name': 'x-ignore-shared', 'features': [ 'unstable' ] }, 'validate-uuid', 'background-snapshot', - 'zero-copy-send', 'postcopy-preempt', 'switchover-ack'] } + 'zero-copy-send', 'postcopy-preempt', 'switchover-ack', + 'dirty-limit'] } ## # @MigrationCapabilityStatus: |