container support not enabled due to required cgroup subsystems not found

[ashutosh mehra]

I am assuming you would be interested in only cgroup related mount points
in /proc/self/mountinfo:

25 18 0:20 / /sys/fs/cgroup ro,nosuid,nodev,noexec shared:8 - tmpfs tmpfs
ro,seclabel,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,nosuid,nodev,noexec,relatime
shared:10 - cgroup cgroup rw,cpuacct,cpu
29 25 0:24 / /sys/fs/cgroup/memory rw,nosuid,nodev,noexec,relatime
shared:11 - cgroup cgroup rw,memory
30 25 0:25 / /sys/fs/cgroup/hugetlb rw,nosuid,nodev,noexec,relatime
shared:12 - cgroup cgroup rw,hugetlb
31 25 0:26 / /sys/fs/cgroup/cpuset rw,nosuid,nodev,noexec,relatime
shared:13 - cgroup cgroup rw,cpuset
32 25 0:27 / /sys/fs/cgroup/perf_event rw,nosuid,nodev,noexec,relatime
shared:14 - cgroup cgroup rw,perf_event
33 25 0:28 / /sys/fs/cgroup/net_cls,net_prio
rw,nosuid,nodev,noexec,relatime shared:15 - cgroup cgroup
rw,net_prio,net_cls
34 25 0:29 / /sys/fs/cgroup/blkio rw,nosuid,nodev,noexec,relatime shared:16
- cgroup cgroup rw,blkio
35 25 0:30 / /sys/fs/cgroup/freezer rw,nosuid,nodev,noexec,relatime
shared:17 - cgroup cgroup rw,freezer
36 25 0:31 / /sys/fs/cgroup/devices rw,nosuid,nodev,noexec,relatime
shared:18 - cgroup cgroup rw,devices
37 25 0:32 / /sys/fs/cgroup/pids rw,nosuid,nodev,noexec,relatime shared:19
- cgroup cgroup rw,pids

Linux distro is RHEL Workstation 7.4
Kernel level - 3.10.0-693.17.1.el7.x86_64

I have cgroup v1.

I will check with Java 11 as well.

Regards,
Ashutosh

On Thu, Mar 15, 2018 at 6:22 PM, Bob Vandette <bob.vandette at oracle.com>
wrote:

> Yes, please send us the contents of /proc/self/mountinfo.
>
> What Linux operating system distro are you running?  What kernel version?
>
> You might want to try the JDK 11 Early Access build.  It provides a bit
> more logging for container detection.
> You will at least see which subsystem was not located.
>
> http://jdk.java.net/11/
>
> Are you running cgroups version 1 or 2?
>
>
> Bob.
>
>
> > On Mar 15, 2018, at 8:27 AM, David Holmes <david.holmes at oracle.com>
> wrote:
> >
> > Moving to hotspot-dev
> >
> > On 15/03/2018 8:51 PM, ashutosh mehra wrote:
> >> When I run  jdk-10+46 build in a docker container, I don't see
> MaxHeapSize
> >> being adjusted based on container memory limit.
> >> Command to run docker container with 2G memory, 2 CPUs:
> >> $ docker run -m2g --memory-swap=2g --cpus=2 -it --rm -v
> >> /home/ashu/data/builds/openjdk/jdk-10+46:/root/jdk-10 ubuntu:16.04
> >> Once inside the container ran the following command:
> >> # /root/jdk-10//bin/java -XX:+UnlockDiagnosticVMOptions
> >> -XX:+PrintFlagsFinal -version | grep MaxHeapSize
> >> Output:
> >>    size_t MaxHeapSize                              = 2015363072
> >>                    {product} {ergonomic}
> >> openjdk version "10" 2018-03-20
> >> OpenJDK Runtime Environment 18.3 (build 10+46)
> >> OpenJDK 64-Bit Server VM 18.3 (build 10+46, mixed mode)
> >> When I used -Xlog:os+container=trace option, I get following
> information:
> >> # /root/jdk-10//bin/java "-Xlog:os+container=trace" -version
> >> [0.001s][trace][os,container] OSContainer::init: Initializing Container
> >> Support
> >> [0.001s][debug][os,container] Required cgroup subsystems not found
> >> openjdk version "10" 2018-03-20
> >> OpenJDK Runtime Environment 18.3 (build 10+46)
> >> OpenJDK 64-Bit Server VM 18.3 (build 10+46, mixed mode)
> >> Following subsystems are present in the docker container:
> >> # ls /sys/fs/cgroup/
> >> blkio  cpu  cpuacct  cpuacct,cpu  cpuset  devices  freezer  hugetlb
> >> memory  net_cls  net_prio  net_prio,net_cls  perf_event  pids  systemd
> >> As far as I understand, JVM is using only memory, cpu and cpuset
> subsystems
> >> which are present in my system. Not sure why is it reporting "Required
> >> cgroup subsystems not found".
> >> Any idea what could be wrong here? Are there other debug options to
> figure
> >> out what is going wrong?
> >
> > What does /proc/self/mountinfo show?
> >
> > David
> >
> >> Regards,
> >> Ashutosh Mehra
>
>