8292541: [Metrics] Reported memory limit may exceed physical machine memory by jmtd · Pull Request #10017 · openjdk/jdk

jmtd · 2022-08-25T09:50:44Z

When the container memory exceeds the physical host's memory, the Java metrics reporting is wrong.

https://bugs.openjdk.org/browse/JDK-8292541

This is the equivalent core-libs fix for Hotspot's JDK-8292083
(#9880)

Progress

Change must be properly reviewed (1 review required, with at least 1 Reviewer)
Change must not contain extraneous whitespace
Commit message must refer to an issue

Issue

JDK-8292541: [Metrics] Reported memory limit may exceed physical machine memory

Reviewers

Thomas Stuefe (@tstuefe - Reviewer) ⚠️ Review applies to ff6990cb
Severin Gehwolf (@jerboaa - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk pull/10017/head:pull/10017
$ git checkout pull/10017

Update a local copy of the PR:
$ git checkout pull/10017
$ git pull https://git.openjdk.org/jdk pull/10017/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 10017

View PR using the GUI difftool:
$ git pr show -t 10017

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/10017.diff

One test for OperatingSystemMXBean and another for -XshowSettings:system, which exercises the Metrics sub-system. extend TestMemoryAwareness to cover OperatingSystemMXBean with bad cgroup memory limit add testMetricsIgnoresMemLimitExceedingPhysicalMemory and refactor Pull the code that establishes host physical max RAM out into a helper function.

Detect when the subsystem limit exceeds physical RAM and treat that situation as "unlimited". Add a private native method to establish physical RAM size. This presently is only likely to work on POSIX systems, but CgroupMetrics are Linux-specific. None the less the precise guards etc. may need adjusting.

bridgekeeper · 2022-08-25T09:52:16Z

👋 Welcome back jdowland! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

openjdk · 2022-08-25T09:54:48Z

@jmtd The following labels will be automatically applied to this pull request:

core-libs
hotspot-runtime

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing lists. If you would like to change these labels, use the /label pull request command.

mlbridge · 2022-08-25T09:58:45Z

Webrevs

src/java.base/linux/classes/jdk/internal/platform/CgroupMetrics.java

src/java.base/linux/native/libjava/CgroupMetrics.c

Thanks Thomas Stuefe

tstuefe

LGTM

src/java.base/linux/classes/jdk/internal/platform/CgroupMetrics.java

openjdk · 2022-08-25T14:37:54Z

@jmtd This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8292541: [Metrics] Reported memory limit may exceed physical machine memory

Reviewed-by: stuefe, sgehwolf

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 2 new commits pushed to the master branch:

3844685: 8292697: ZGC: Hangs when almost out of metaspace memory
2b80349: 8292669: IGV: Search not useable when in Overflow Toolbar

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

As you do not have Committer status in this project an existing Committer must agree to sponsor your change. Possible candidates are the reviewers of this PR (@tstuefe, @jerboaa) but any other Committer may sponsor as well.

➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

test/hotspot/jtreg/containers/docker/TestMemoryAwareness.java

jerboaa

Looks good.

This is relied upon for tests in test/hotspot/jtreg/containers/docker/TestMemoryAwareness.java

jmtd · 2022-08-25T19:57:39Z

/integrate

openjdk · 2022-08-25T20:00:31Z

@jmtd
Your change (at version 1bf3aa3) is now ready to be sponsored by a Committer.

jerboaa

Sorry, but this last change is a hack.

src/hotspot/os/linux/cgroupSubsystem_linux.cpp

For 8292541, I wrote two further tests that used the same technique as testContainerMemExceedsPhysical to establish baseline physical RAM. Rework testContainerMemExceedsPhysical to use the shared variable hostMaxMem rather than recalculate the value itself.

jmtd · 2022-08-26T13:17:46Z

Now that #9880 has been merged the hack is gone and the tests can match against the log lines to establish base line physical RAM. There are three tests that use this now. In cc8fdf3 for this PR I've adjusted the first test (merged already) to share the established baseline physical RAM value rather than calculate it again.

@jerboaa WDYT now? And thanks for all your support!

test/hotspot/jtreg/containers/docker/TestMemoryAwareness.java

jerboaa

OK.

jmtd · 2022-08-26T14:39:19Z

/integrate

openjdk · 2022-08-26T14:40:20Z

@jmtd
Your change (at version 0f37be8) is now ready to be sponsored by a Committer.

jerboaa · 2022-08-26T16:20:59Z

/sponsor

openjdk · 2022-08-26T16:22:25Z

Going to push as commit 9a0d1e7.
Since your change was applied there have been 3 commits pushed to the master branch:

c74b6d4: 8292562: (fc) Use copy_file_range in FileChannel::transferTo on Linux
3844685: 8292697: ZGC: Hangs when almost out of metaspace memory
2b80349: 8292669: IGV: Search not useable when in Overflow Toolbar

Your commit was automatically rebased without conflicts.

openjdk · 2022-08-26T16:22:41Z

@jerboaa @jmtd Pushed as commit 9a0d1e7.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

jmtd added 2 commits August 25, 2022 10:50

openjdk bot added the rfr Pull request is ready for review label Aug 25, 2022

openjdk bot added hotspot-runtime hotspot-runtime-dev@openjdk.org core-libs core-libs-dev@openjdk.org labels Aug 25, 2022

avoid calling subsystem.getMemoryLimit twice

806a084

tstuefe reviewed Aug 25, 2022

View reviewed changes

src/java.base/linux/classes/jdk/internal/platform/CgroupMetrics.java Outdated Show resolved Hide resolved

src/java.base/linux/native/libjava/CgroupMetrics.c Show resolved Hide resolved

Address nit

ff6990c

Thanks Thomas Stuefe

tstuefe approved these changes Aug 25, 2022

View reviewed changes

jerboaa reviewed Aug 25, 2022

View reviewed changes

openjdk bot added the ready Pull request is ready to be integrated label Aug 25, 2022

jmtd added 2 commits August 25, 2022 16:24

Address style nits

85fa402

use pre-defined constant over magic number

01d07ab

jmtd commented Aug 25, 2022

View reviewed changes

test/hotspot/jtreg/containers/docker/TestMemoryAwareness.java Show resolved Hide resolved

jerboaa approved these changes Aug 25, 2022

View reviewed changes

Add a log-line for total physical memory

1bf3aa3

This is relied upon for tests in test/hotspot/jtreg/containers/docker/TestMemoryAwareness.java

openjdk bot added the sponsor Pull request is ready to be sponsored label Aug 25, 2022

jerboaa suggested changes Aug 26, 2022

View reviewed changes

src/hotspot/os/linux/cgroupSubsystem_linux.cpp Show resolved Hide resolved

jmtd added 2 commits August 26, 2022 13:58

Merge remote-tracking branch 'origin/master' into 8292541-cgroup-metrics

e72e50d

openjdk bot removed the sponsor Pull request is ready to be sponsored label Aug 26, 2022

jerboaa reviewed Aug 26, 2022

View reviewed changes

test/hotspot/jtreg/containers/docker/TestMemoryAwareness.java Outdated Show resolved Hide resolved

Pass hostMaxMem to relevant methods as a parameter

0f37be8

jerboaa approved these changes Aug 26, 2022

View reviewed changes

openjdk bot added the sponsor Pull request is ready to be sponsored label Aug 26, 2022

openjdk bot added the integrated Pull request has been integrated label Aug 26, 2022

openjdk bot closed this Aug 26, 2022

openjdk bot removed ready Pull request is ready to be integrated rfr Pull request is ready for review sponsor Pull request is ready to be sponsored labels Aug 26, 2022

Conversation

jmtd commented Aug 25, 2022 • edited by openjdk bot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Progress

Issue

Reviewers

Reviewing

Uh oh!

bridgekeeper bot commented Aug 25, 2022

Uh oh!

openjdk bot commented Aug 25, 2022

Uh oh!

mlbridge bot commented Aug 25, 2022 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Webrevs

Uh oh!

Uh oh!

Uh oh!

tstuefe left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

openjdk bot commented Aug 25, 2022 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Uh oh!

jerboaa left a comment

Choose a reason for hiding this comment

Uh oh!

jmtd commented Aug 25, 2022

Uh oh!

openjdk bot commented Aug 25, 2022

Uh oh!

jerboaa left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

jmtd commented Aug 26, 2022

Uh oh!

Uh oh!

jerboaa left a comment

Choose a reason for hiding this comment

Uh oh!

jmtd commented Aug 26, 2022

Uh oh!

openjdk bot commented Aug 26, 2022

Uh oh!

jerboaa commented Aug 26, 2022

Uh oh!

openjdk bot commented Aug 26, 2022

Uh oh!

openjdk bot commented Aug 26, 2022

Uh oh!

Reviewers

Assignees

Labels

Milestone

Development

Uh oh!

3 participants

jmtd commented Aug 25, 2022 •

edited by openjdk bot

Loading

mlbridge bot commented Aug 25, 2022 •

edited

Loading

openjdk bot commented Aug 25, 2022 •

edited

Loading