Bug 1330598
| Summary: | lxc: /proc/meminfo / free 'total' becomes huge (9007199254740991) | ||
|---|---|---|---|
| Product: | [Community] Virtualization Tools | Reporter: | Maxim <kolomaxes> |
| Component: | libvirt | Assignee: | Libvirt Maintainers <libvirt-maint> |
| Status: | CLOSED DEFERRED | QA Contact: | |
| Severity: | unspecified | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | unspecified | CC: | berrange, crobinso |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2024-12-17 12:04:57 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
Discussion here: http://www.redhat.com/archives/libvirt-users/2016-March/msg00112.html http://www.redhat.com/archives/libvirt-users/2016-April/msg00101.html Thank you for reporting this issue to the libvirt project. Unfortunately we have been unable to resolve this issue due to insufficient maintainer capacity and it will now be closed. This is not a reflection on the possible validity of the issue, merely the lack of resources to investigate and address it, for which we apologise. If you none the less feel the issue is still important, you may choose to report it again at the new project issue tracker https://gitlab.com/libvirt/libvirt/-/issues The project also welcomes contribution from anyone who believes they can provide a solution. |
Description of problem: Command "free" inside LXC container show 8PTb (9007199254740991) total memory. Version-Release number of selected component (if applicable): libvirt 1.3.2 build from sources with next options --without qemu \ --without xen \ --without openvz \ --without vmware \ --without esx \ --without parallels \ --without bhyve \ --without uml \ --without vbox \ --without selinux \ --with lxc \ --with macvtap \ --without storage-rbd \ --with capng Run on CentOS Linux release 7.2.1511 (Core), kernel 3.10.0-327.13.1.el7.x86_64 How reproducible: permanently Steps to Reproduce: 1. create and start LXC container with memory limit 1G 2. create on top hardware node systemd service: # cat /usr/lib/systemd/system/true.service [Unit] Description=simple test [Service] Type=simple ExecStart=/bin/true [Install] WantedBy=multi-user.target 3. Enable service first time, disable and start: # systemctl enable /usr/lib/systemd/system/true.service Created symlink from /etc/systemd/system/multi-user.target.wants/true.service to /usr/lib/systemd/system/true.service. # systemctl disable true.service Removed symlink /etc/systemd/system/multi-user.target.wants/true.service. # systemctl start true.service Actual results: inside container [root@LXC]# free total used free shared buff/cache available Mem: 9007199254740991 193168 9007199254226743 11112 321080 9007199254226743 Swap: 0 0 0 Expected results: inside container [root@LXC]# free total used free shared buff/cache available Mem: 1048576 7668 1022576 11112 18332 1022576 Swap: 1048576 0 1048576 Additional info: while broken, PID of libvirt LXC process removed from cgroups. Example. Before failure: [root@node01]# cat /sys/fs/cgroup/memory/machine.slice/machine-lxc\\x2d7445\\x2dtst\\x2dmxs2.test.scope/memory.limit_in_bytes 1073741824 4) Check list of pid in cgroups (it's IMPOTANT moment): [root@node01]# cat /sys/fs/cgroup/memory/machine.slice/machine-lxc\\x2d7445\\x2dtst\\x2dmxs2.test.scope/tasks 7445 7446 7480 7506 7510 7511 7512 7529 7532 7533 7723 7724 8251 8253 10455 First PID 7445 - it's pid of libvirt process for container: # ps ax | grep 7445 7445 ? Sl 0:00 /usr/libexec/libvirt_lxc --name tst-mxs2.test --console 21 --security=none --handshake 24 --veth macvlan5 [root@node01]# virsh list Id Name State ---------------------------------------------------- 7445 tst-mxs2.test running After failure: root@node01]# cat /sys/fs/cgroup/memory/machine.slice/machine-lxc\\x2d7445\\x2dtst\\x2dmxs2.test.scope/tasks 7446 7480 7506 7510 7511 7512 7529 7532 7533 7723 7724 8251 8253 After start disabled systemd service, from task list removed libvirt PID 7445. It's mean that inside LXC limit real still worked, 7446 - it's PID of /sbin/init inside container. Workaround: Broken only fuse mount. It's positive news - process inside container even in case 8Ptb can't allocate more memory that set in cgroups. But negative news - that some java based sotfware (as puppetdb in our case) plan self strategy based on 8Ptb memory and collapsed after reach real limit. Run cglassify or equivalent, example: [root@node01]# echo 7445 > /sys/fs/cgroup/memory/machine.slice/machine-lxc\\x2d7445\\x2dtst\\x2dmxs2.test.scope/tasks