----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/53641/ -----------------------------------------------------------
Review request for mesos, Gilbert Song, Jie Yu, Qian Zhang, and Jiang Yan Xu. Repository: mesos Description ------- Refactored `CgroupsAnyHierarchyTest` test cases. Diffs ----- src/tests/containerizer/cgroups_tests.cpp 0afaec6ae948cabf1472bf01103210d8f9809cb1 Diff: https://reviews.apache.org/r/53641/diff/ Testing ------- This patch attempts to refactor `CgroupsAnyHierarchy` test cases to use a different hierarchy structure. If `cpu` have been mounted at `/sys/fs/cgroup/cpu`, it would try to mount all rest subsystems at `/tmp/mesos_test_cgroup`. I have several concerns about this proposal. 1. Mount `cpu` at `/sys/fs/cgroup/cpu` while mount `memory` or any other subsystems at `/tmp/mesos_test_cgroup` would fail if cgroups is managed by systemd. I test this in CentOS 7. ``` ## cpu,cpuacct have been mounted # cat /proc/self/mountinfo |grep cgroup 25 18 0:20 / /sys/fs/cgroup ro,nosuid,nodev,noexec shared:8 - tmpfs tmpfs ro,mode=755 26 25 0:21 / /sys/fs/cgroup/systemd rw,nosuid,nodev,noexec,relatime shared:9 - cgroup cgroup rw,xattr,release_agent=/usr/lib/systemd/systemd-cgroups-agent,name=systemd 28 25 0:23 / /sys/fs/cgroup/cpu,cpuacct rw,relatime shared:10 - cgroup cgroup rw,cpuacct,cpu ## Mount rest subsystems would failed. # mount -t cgroup -o rw,memory,devices cgroup /tmp/mesos_test_cgroup mount: cgroup is already mounted or /tmp/mesos_test_cgroup busy cgroup is already mounted on /sys/fs/cgroup/systemd cgroup is already mounted on /sys/fs/cgroup/cpu,cpuacct ``` 2. I think in current code base, we suppose all the hierarchies under the same directory, instead of supposing that some hierarchies are mounted at `/sys/fs/cgroup/xxx` while some hierarchies are mounted at `/tmp/mesos_test_cgroup`. This is what we suppose in `ContainerizerTest<slave::MesosContainerizer>` as well. 3. As we see in this patch, change to put hierarchies under different folders looks messy, compare to use a single folder for all cgroup subsystems. cgroups-v2 unified all subsystems under a same hierarchy, which don't allow us mount `cpu` at `/sys/fs/cgroup/cpu` while mount `memory` at `/tmp/mesos_test_cgroup` as well. Thanks, haosdent huang
