[PATCH QEMU 3/3] MAINTAINERS: Add Hyman Huang as maintainer

[PATCH QEMU 3/3] MAINTAINERS: Add Hyman Huang as maintainer

[~hyman]

From: Hyman Huang(黄勇) <yong.huang@smartx.com>

I've built interests in dirty-limit and dirty page rate
features and also have been working on projects related
to this subsystem.

Self-recommand myself as a maintainer for this subsystem
so that I can help to improve the dirty-limit algorithm
and review the patches about dirty page rate.

Signed-off-by: Hyman Huang(黄勇) <yong.huang@smartx.com>
---
 MAINTAINERS | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 12e59b6b27..d4b1c91096 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3437,6 +3437,15 @@ F: hw/core/clock-vmstate.c
 F: hw/core/qdev-clock.c
 F: docs/devel/clocks.rst
 
+Dirty-limit and dirty page rate feature
+M: Hyman Huang <yong.huang@smartx.com>
+S: Maintained
+F: softmmu/dirtylimit.c
+F: include/sysemu/dirtylimit.h
+F: migration/dirtyrate.c
+F: migration/dirtyrate.h
+F: include/sysemu/dirtyrate.h
+
 Usermode Emulation
 ------------------
 Overall usermode emulation
-- 
2.38.5

[PATCH QEMU 1/3] qapi: Reformat the dirty-limit migration doc comments

[~hyman]

From: Hyman Huang(黄勇) <yong.huang@smartx.com>

Reformat the dirty-limit migration doc comments to conform
to current conventions as commit a937b6aa739 (qapi: Reformat
doc comments to conform to current conventions).

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Hyman Huang(黄勇) <yong.huang@smartx.com>
---
 qapi/migration.json | 69 ++++++++++++++++++++++-----------------------
 1 file changed, 34 insertions(+), 35 deletions(-)

diff --git a/qapi/migration.json b/qapi/migration.json
index 6b49593d2f..a74ade4d72 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -258,17 +258,17 @@
 #     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
-#                              dirty ring memory size divided by average dirty page rate
-#                              of virtual CPU, which can be used to observe the average
-#                              memory load of virtual CPU indirectly. Note that zero
-#                              means guest doesn't dirty memory (since 8.1)
+# @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) for each dirty ring full round. The
+#     value equals the dirty ring memory size divided by the 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)
 #
 # Since: 0.14
 ##
@@ -519,15 +519,14 @@
 #     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)
+# @dirty-limit: If enabled, migration will use the dirty-limit
+#     algorithim to throttle down guest instead of auto-converge
+#     algorithim. Throttle algorithim only works when vCPU's dirtyrate
+#     greater than 'vcpu-dirty-limit', read processes in guest os
+#     aren't penalized any more, so this algorithim 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 algorithim.  (Since 8.1)
 #
 # Features:
 #
@@ -822,17 +821,17 @@
 #     Nodes are mapped to their block device name if there is one, and
 #     to their node name otherwise.  (Since 5.2)
 #
-# @x-vcpu-dirty-limit-period: Periodic time (in milliseconds) of dirty limit during
-#                             live migration. Should be in the range 1 to 1000ms,
-#                             defaults to 1000ms. (Since 8.1)
+# @x-vcpu-dirty-limit-period: Periodic time (in milliseconds) of dirty
+#     limit during live migration. Should be in the range 1 to 1000ms.
+#     Defaults to 1000ms.  (Since 8.1)
 #
 # @vcpu-dirty-limit: Dirtyrate limit (MB/s) during live migration.
-#                    Defaults to 1. (Since 8.1)
+#     Defaults to 1.  (Since 8.1)
 #
 # Features:
 #
 # @unstable: Members @x-checkpoint-delay and @x-vcpu-dirty-limit-period
-#            are experimental.
+#     are experimental.
 #
 # Since: 2.4
 ##
@@ -988,17 +987,17 @@
 #     Nodes are mapped to their block device name if there is one, and
 #     to their node name otherwise.  (Since 5.2)
 #
-# @x-vcpu-dirty-limit-period: Periodic time (in milliseconds) of dirty limit during
-#                             live migration. Should be in the range 1 to 1000ms,
-#                             defaults to 1000ms. (Since 8.1)
+# @x-vcpu-dirty-limit-period: Periodic time (in milliseconds) of dirty
+#     limit during live migration. Should be in the range 1 to 1000ms.
+#     Defaults to 1000ms.  (Since 8.1)
 #
 # @vcpu-dirty-limit: Dirtyrate limit (MB/s) during live migration.
-#                    Defaults to 1. (Since 8.1)
+#     Defaults to 1.  (Since 8.1)
 #
 # Features:
 #
 # @unstable: Members @x-checkpoint-delay and @x-vcpu-dirty-limit-period
-#            are experimental.
+#     are experimental.
 #
 # TODO: either fuse back into MigrationParameters, or make
 #     MigrationParameters members mandatory
@@ -1191,17 +1190,17 @@
 #     Nodes are mapped to their block device name if there is one, and
 #     to their node name otherwise.  (Since 5.2)
 #
-# @x-vcpu-dirty-limit-period: Periodic time (in milliseconds) of dirty limit during
-#                             live migration. Should be in the range 1 to 1000ms,
-#                             defaults to 1000ms. (Since 8.1)
+# @x-vcpu-dirty-limit-period: Periodic time (in milliseconds) of dirty
+#     limit during live migration. Should be in the range 1 to 1000ms.
+#     Defaults to 1000ms.  (Since 8.1)
 #
 # @vcpu-dirty-limit: Dirtyrate limit (MB/s) during live migration.
-#                    Defaults to 1. (Since 8.1)
+#     Defaults to 1.  (Since 8.1)
 #
 # Features:
 #
 # @unstable: Members @x-checkpoint-delay and @x-vcpu-dirty-limit-period
-#            are experimental.
+#     are experimental.
 #
 # Since: 2.4
 ##
-- 
2.38.5

[PATCH QEMU 2/3] qapi: Craft the dirty-limit capability comment

[~hyman]

From: Hyman Huang(黄勇) <yong.huang@smartx.com>

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Hyman Huang(黄勇) <yong.huang@smartx.com>
---
 qapi/migration.json | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/qapi/migration.json b/qapi/migration.json
index a74ade4d72..62ab151da2 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -519,14 +519,11 @@
 #     are present.  'return-path' capability must be enabled to use
 #     it.  (since 8.1)
 #
-# @dirty-limit: If enabled, migration will use the dirty-limit
-#     algorithim to throttle down guest instead of auto-converge
-#     algorithim. Throttle algorithim only works when vCPU's dirtyrate
-#     greater than 'vcpu-dirty-limit', read processes in guest os
-#     aren't penalized any more, so this algorithim 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 algorithim.  (Since 8.1)
+# @dirty-limit: If enabled, migration will throttle vCPUs as needed to
+#     keep their dirty page rate within @vcpu-dirty-limit.  This can
+#     improve responsiveness of large guests during live migration,
+#     and can result in more stable read performance.  Requires KVM
+#     with accelerator property "dirty-ring-size" set.  (Since 8.1)
 #
 # Features:
 #
-- 
2.38.5

[PATCH QEMU 0/3] migration: craft the doc comments

[~hyman]

Hi, Markus, Juan.

Please review the version 2, thanks.

v2:
- split the first commit in v1 into 2
- add commit message of commit:
  MAINTAINERS: Add Hyman Huang as maintainer

Yong

Hyman Huang(黄勇) (3):
  qapi: Reformat the dirty-limit migration doc comments
  qapi: Craft the dirty-limit capability comment
  MAINTAINERS: Add Hyman Huang as maintainer

 MAINTAINERS         |  9 +++++++
 qapi/migration.json | 66 +++++++++++++++++++++------------------------
 2 files changed, 40 insertions(+), 35 deletions(-)

-- 
2.38.5

Re: [PATCH QEMU 3/3] MAINTAINERS: Add Hyman Huang as maintainer

[Peter Xu]

On Thu, Jul 27, 2023 at 02:10:09AM +0800, ~hyman wrote:
> From: Hyman Huang(黄勇) <yong.huang@smartx.com>
> 
> I've built interests in dirty-limit and dirty page rate
> features and also have been working on projects related
> to this subsystem.
> 
> Self-recommand myself as a maintainer for this subsystem
> so that I can help to improve the dirty-limit algorithm
> and review the patches about dirty page rate.
> 
> Signed-off-by: Hyman Huang(黄勇) <yong.huang@smartx.com>

Acked-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu

Re: [PATCH QEMU 3/3] MAINTAINERS: Add Hyman Huang as maintainer

[Markus Armbruster]

Recommend to tweak the subject to

    MAINTAINERS: Add section "TITLE"

where TITLE is whatever you use in MAINTAINERS, provided it's short
enough to fit.

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

> From: Hyman Huang(黄勇) <yong.huang@smartx.com>
>
> I've built interests in dirty-limit and dirty page rate

Recommend to drop the dash.

> features and also have been working on projects related
> to this subsystem.
>
> Self-recommand myself as a maintainer for this subsystem

"Add myself as ..."

> so that I can help to improve the dirty-limit algorithm
> and review the patches about dirty page rate.
>
> Signed-off-by: Hyman Huang(黄勇) <yong.huang@smartx.com>
> ---
>  MAINTAINERS | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 12e59b6b27..d4b1c91096 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3437,6 +3437,15 @@ F: hw/core/clock-vmstate.c
>  F: hw/core/qdev-clock.c
>  F: docs/devel/clocks.rst
>  
> +Dirty-limit and dirty page rate feature

Suggest

   Migration dirty limit and dirty page rate

> +M: Hyman Huang <yong.huang@smartx.com>
> +S: Maintained
> +F: softmmu/dirtylimit.c
> +F: include/sysemu/dirtylimit.h
> +F: migration/dirtyrate.c
> +F: migration/dirtyrate.h
> +F: include/sysemu/dirtyrate.h
> +

Should this go right after section "Migration"?  Or are there other
applications?

>  Usermode Emulation
>  ------------------
>  Overall usermode emulation