Hyman Huang <huang...@chinatelecom.cn> writes: > 在 2022/10/2 2:31, Markus Armbruster 写道: >> huang...@chinatelecom.cn writes: >> >>> From: Hyman Huang(黄勇) <huang...@chinatelecom.cn> >>> >>> Export dirty limit throttle time and estimated ring full >>> time, through which we can observe the process of dirty >>> limit during live migration. >>> >>> Signed-off-by: Hyman Huang(黄勇) <huang...@chinatelecom.cn> >> [...] >> >>> diff --git a/qapi/migration.json b/qapi/migration.json >>> index bc4bc96..c263d54 100644 >>> --- a/qapi/migration.json >>> +++ b/qapi/migration.json >>> @@ -242,6 +242,12 @@ >>> # Present and non-empty when migration is blocked. >>> # (since 6.0) >>> # >>> +# @dirty-limit-throttle-us-per-full: Throttle time (us) during the period >>> of >>> +# dirty ring full (since 7.0) >>> +# >>> +# @dirty-limit-us-ring-full: Estimated periodic time (us) of dirty ring >>> full. >>> +# (since 7.0) >>> +# >> >> Can you explain what is measured here a bit more verbosely? > > The two fields of migration info aims to export dirty-limit throttle time so > that upper apps can check out the process of live migration, > like 'cpu-throttle-percentage'. > > The commit "tests: Add migration dirty-limit capability test" make use of the > 'dirty-limit-throttle-us-per-full' to checkout if dirty-limit has > started, the commit "tests/migration: Introduce dirty-limit into guestperf" > introduce the two field so guestperf tools also show the > process of dirty-limit migration. > > And i also use qmp_query_migrate to observe the migration by checkout these > two fields. > > I'm not sure if above explantation is what you want exactly, please be free > to start any discussion about this features.
You explained use cases, which is always welcome. I'm trying to understand the two new members' meaning, i.e. what exactly is being measured. For existing @cpu-throttle-percentage, the doc comment tells me: "percentage of time guest cpus are being throttled during auto-converge." For the your new members, the doc comment tries to tell me, but it doesn't succeed. If you explain what is being measured more verbosely, we may be able to improve the doc comment.
