[jdk17u-dev] RFR: 8347129: cpuset cgroups controller is required for no good reason

[Severin Gehwolf]

Clean backport from JDK 21u. Should be low risk. Affects newer development systems on Linux, like F41+, where memory limits aren't properly detected.

Container tests fail on affected systems (before the patch):

Passed: containers/cgroup/CgroupSubsystemFactory.java
Passed: containers/cgroup/PlainRead.java
Passed: containers/docker/DockerBasicTest.java
Passed: containers/docker/ShareTmpDir.java
Passed: containers/docker/TestContainerInfo.java
FAILED: containers/docker/TestCPUAwareness.java
FAILED: containers/docker/TestCPUSets.java
Passed: containers/docker/TestJcmd.java
Passed: containers/docker/TestJcmdWithSideCar.java
FAILED: containers/docker/TestJFREvents.java
Passed: containers/docker/TestJFRNetworkEvents.java
Passed: containers/docker/TestJFRWithJMX.java
FAILED: containers/docker/TestLimitsUpdating.java
FAILED: containers/docker/TestMemoryAwareness.java
Passed: containers/docker/TestMemoryWithCgroupV1.java
FAILED: containers/docker/TestMisc.java
FAILED: containers/docker/TestPids.java
Test results: passed: 10; failed: 7; skipped: 1


Caused by:

 stdout: [[0.000s][trace][os,container] OSContainer::init: Initializing Container Support
[0.000s][debug][os,container] Detected optional pids controller entry in /proc/cgroups
[0.000s][debug][os,container] controller cpu is not enabled

[0.000s][debug][os,container] One or more required controllers disabled at kernel level.
openjdk version "17.0.18-internal" 2026-01-20
OpenJDK Runtime Environment (fastdebug build 17.0.18-internal+0-adhoc.sgehwolf.jdk17u-dev)
OpenJDK 64-Bit Server VM (fastdebug build 17.0.18-internal+0-adhoc.sgehwolf.jdk17u-dev, mixed mode, sharing)
];
 stderr: []
 exitValue = 0

java.lang.RuntimeException: 'active_processor_count.*1' missing from stdout/stderr


Testing after the patch (on an affected system):

Passed: containers/cgroup/CgroupSubsystemFactory.java
Passed: containers/cgroup/PlainRead.java
Passed: containers/docker/DockerBasicTest.java
Passed: containers/docker/ShareTmpDir.java
Passed: containers/docker/TestContainerInfo.java
Passed: containers/docker/TestCPUAwareness.java
Passed: containers/docker/TestCPUSets.java
Passed: containers/docker/TestJcmd.java
Passed: containers/docker/TestJcmdWithSideCar.java
Passed: containers/docker/TestJFREvents.java
Passed: containers/docker/TestJFRNetworkEvents.java
Passed: containers/docker/TestJFRWithJMX.java
Passed: containers/docker/TestLimitsUpdating.java
Passed: containers/docker/TestMemoryAwareness.java
Passed: containers/docker/TestMemoryWithCgroupV1.java
Passed: containers/docker/TestMisc.java
Passed: containers/docker/TestPids.java
Test results: passed: 17


After patch on cgroup v1 (no-op there):

Passed: containers/cgroup/CgroupSubsystemFactory.java
Passed: containers/cgroup/PlainRead.java
Passed: containers/docker/DockerBasicTest.java
Passed: containers/docker/ShareTmpDir.java
Passed: containers/docker/TestContainerInfo.java
Passed: containers/docker/TestCPUAwareness.java
Passed: containers/docker/TestCPUSets.java
Passed: containers/docker/TestJcmd.java
Passed: containers/docker/TestJcmdWithSideCar.java
Passed: containers/docker/TestJFREvents.java
Passed: containers/docker/TestJFRNetworkEvents.java
Passed: containers/docker/TestJFRWithJMX.java
Passed: containers/docker/TestLimitsUpdating.java
Passed: containers/docker/TestMemoryAwareness.java
Passed: containers/docker/TestMemoryWithCgroupV1.java
Passed: containers/docker/TestMisc.java
Passed: containers/docker/TestPids.java
Test results: passed: 17; skipped: 1

-------------

Commit messages:
 - Backport be245be258cda7e06366b4051eec24ad6df04f20

Changes: https://git.openjdk.org/jdk17u-dev/pull/4009/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=4009&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8347129
  Stats: 6 lines in 1 file changed: 2 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/4009.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/4009/head:pull/4009

PR: https://git.openjdk.org/jdk17u-dev/pull/4009