在 2021/11/22 17:10, Markus Armbruster 写道:
Hyman Huang <[email protected]> writes:
=E5=9C=A8 2021/11/22 15:35, Markus Armbruster =E5=86=99=E9=81=93:
[email protected] writes:
From: Hyman Huang(=E9=BB=84=E5=8B=87) <[email protected]>
implement dirtyrate calculation periodically basing on
dirty-ring and throttle vCPU until it reachs the quota
dirtyrate given by user.
introduce qmp commands set-dirty-limit/cancel-dirty-limit to
set/cancel dirty limit on vCPU.
Please start sentences with a capital letter.
Ok，i'll check the syntax problem next version.
Signed-off-by: Hyman Huang(黄勇) <[email protected]>
[...]
diff --git a/qapi/misc.json b/qapi/misc.json
index 358548a..98e6001 100644
--- a/qapi/misc.json
+++ b/qapi/misc.json
@@ -527,3 +527,42 @@
'data': { '*option': 'str' },
'returns': ['CommandLineOptionInfo'],
'allow-preconfig': true }
+
+##
+# @set-dirty-limit:
+#
+# This command could be used to cap the vCPU memory load, which is also
+# refered as dirtyrate. One should use "calc-dirty-rate" with "dirty-ring"
+# and to calculate vCPU dirtyrate and query it with "query-dirty-rate".
+# Once getting the vCPU current dirtyrate, "set-dirty-limit" can be used
+# to set the upper limit of dirtyrate for the interested vCPU.
"dirtyrate" is not a word. Let's spell it "dirty page rate", for
consistency with the documentation in migration.json.
Ok, sounds good.
Regarding "One should use ...": sounds like you have to run
calc-dirty-rate with argument @mode set to @dirty-ring before this
command. Correct? What happens when you don't? set-dirty-limit fails?
You didn't answer this question.
set-dirty-limit doesn't do any pre-check about if calc-dirty-rate has
executed, so it doesn't fail.
Since only executing calc-dirty-rate with dirty-ring mode can we get the
vCPU dirty page rate currently(while the dirty-bitmap only get the vm
dirty page rate), "One should use ..." maybe misleading, what i actually
want to say is "One should use the dirty-ring mode to calculate the vCPU
dirty page rate".
Do you also have to run query-dirty-rate before this command?
Actually no, i'll clarify the usage next verison.
Regarding "dirty-ring": is this merely a limitation of the
implementation, i.e. other modes could be made to work if we cared, or
is it more fundamental?
Speaking of migration.json: should these commands be defined there, next
to calc-dirty-rate and query-dirty-rate?
I'm struggling too because these commands will be used in migration but
it is vCPU they handle.
I think migration.json is more about CPUs than misc.json is. Let's add
the new commands to migration.json if migration maintainers are okay
with it.
[...]
--
Best regard
Hyman Huang(黄勇)
