Provide distinct cgroup VM overcommit accounting and handling using the memory resource controller.
Patchset against latest Linus git tree. This patchset allows to set different per-cgroup overcommit rules and, according to them, it's possible to return a memory allocation failure (ENOMEM) to the applications, instead of always triggering the OOM killer via mem_cgroup_out_of_memory() when cgroup memory limits are exceeded. Default overcommit settings are taken from vm.overcommit_memory and vm.overcommit_ratio sysctl values. Child cgroups initially inherits the VM overcommit parent's settings. Cgroup overcommit settings can be overridden using memory.overcommit_memory and memory.overcommit_ratio files under the cgroup filesystem. For example: 1. Initialize a cgroup with 50MB memory limit: # mount -t cgroup none /cgroups -o memory # mkdir /cgroups/0 # /bin/echo $$ > /cgroups/0/tasks # /bin/echo 50M > /cgroups/0/memory.limit_in_bytes 2. Use the "never overcommit" policy with 50% ratio: # /bin/echo 2 > /cgroups/0/memory.overcommit_memory # /bin/echo 50 > /cgroups/0/memory.overcommit_ratio Assuming we have no swap space, cgroup 0 can allocate up to 25MB of virtual memory. If that limit is exceeded all the further allocation attempts made by userspace applications will receive a -ENOMEM. 4. Show committed VM statistics: # cat /cgroups/0/memory.overcommit_as CommitLimit: 25600 kB Committed_AS: 9844 kB 5. Use "always overcommmit": # /bin/echo 1 > /cgroups/0/memory.overcommit_memory This is very similar to the default memory controller configuration: overcommit is allowed, but when there's no more available memory oom-killer is invoked. TODO: - shared memory is not taken in account (i.e. files in tmpfs) -Andrea _______________________________________________ Containers mailing list [EMAIL PROTECTED] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list Devel@openvz.org https://openvz.org/mailman/listinfo/devel