On Wed, 25 May 2022 15:51:04 GMT, Ioi Lam <ik...@openjdk.org> wrote: >> This PR fixes a bug found on an Ubuntu host that's mostly running with >> cgroupv2, but there's a controller (freezer) that is mounted in cgroupv1 >> mode. >> >> The container support code in the VM and JDK checks if we have >> simultaneously mounted v1 and v2 containers. If so, we revert to "hybrid" >> mode (which is essentially v1). >> >> However, the "hybrid checks" only considers the following controllers that >> Java cares about: >> >> - cpu >> - cpuacct >> - cpuset >> - blkio >> - memory >> - pids >> >> If only "freezer" is mounted in v1 mode, Java will start in V2 mode. Later, >> when `setCgroupV2Path()` sees the first line in /proc/self/cgroup, it runs >> into the assert. >> >> >> $ cat /proc/self/cgroup >> 1:freezer:/ >> 0::/user.slice/user-1001.slice/session-85.scope >> >> >> The fix is simple -- when we get to `setCgroupV2Path()`, we have already >> decided that the system has not mounted any v1 controllers that we care >> about, so we should just ignore all the v1 controllers (which has a >> non-empty name). > > Ioi Lam has updated the pull request incrementally with one additional commit > since the last revision: > > fixed comments
src/java.base/linux/classes/jdk/internal/platform/CgroupSubsystemFactory.java line 149: > 147: // other controllers (such as freezer) are ignored and > 148: // are not considered in the checks below for > 149: // anyCgroupsV1Controller/anyCgroupsV1Controller. It still has the `anyCgroupsV1Controller/anyCgroupsV1Controller` typo. Not **V1** twice? ------------- PR: https://git.openjdk.java.net/jdk/pull/8858
