On Wed, 15 Oct 2025 14:18:41 GMT, SendaoYan <[email protected]> wrote:
> Hi all,
>
> The sub-test failcount in
> jdk/internal/platform/docker/TestDockerMemoryMetrics.java requires swap
> memory enable on the test host. But the swap memory check introduced by
> JDK-8264524 do not work correctly, because it's missing jvm option
> '-XX:+AlwaysPreTouch', shows as below. This PR add jvm option
> '-XX:+AlwaysPreTouch' to make the swap memory check work correctly, and use
> jtreg.SkippedException instead of print waring when this test can not execute.
>
> Change has been verified locally on linux-x64. Test fix only, no risk.
>
>
>> free -h
> total used free shared buff/cache available
> Mem: 751Gi 513Gi 229Gi 5.0Mi 8.4Gi 234Gi
> Swap: 0B 0B 0B
>
>
> Without jvm option -XX:+AlwaysPreTouch, the 'java -Xms128m -Xmx128m -version'
> can start successfully:
>
>> docker run --rm --memory=128m
>> jdk-internal:test-jdk-internal-platform-docker-TestDockerMemoryMetrics-metrics-memory
>> /jdk/bin/java -Xms128m -Xmx128m -version
> openjdk version "26" 2026-03-17
> OpenJDK Runtime Environment HJDK-0 (build 26+-42b2999c)
> OpenJDK 64-Bit Server VM HJDK-0 (build 26+-42b2999c, mixed mode, sharing)
>
>
> With jvm option -XX:+AlwaysPreTouch, the 'java -XX:+AlwaysPreTouch -Xms128m
> -Xmx128m -version' can not start and killed by docker(return code is 137):
>
>> docker run --rm --memory=128m
>> jdk-internal:test-jdk-internal-platform-docker-TestDockerMemoryMetrics-metrics-memory
>> /jdk/bin/java -XX:+AlwaysPreTouch -Xms128m -Xmx128m -version ; echo $?
> 137
Please amend the comment on line 114 to something like this:
// Check whether swapping really works for this test
// On some systems there is no swap space enabled. And running
// 'java -Xms{mem-limit} -Xmx{mem-limit} -XX:+AlwaysPreTouch -version'
// would fail due to swap space size being 0. Note that when swap is
// properly enabled on the system the container gets the same amount
// of swap as is configured for memory. Thus, 2x{mem-limit} is the
actual
// memory and swap bound for this pre-test.
-------------
PR Review: https://git.openjdk.org/jdk/pull/27823#pullrequestreview-3345562755
