Bug 1300781
| Summary: | Incorrect memory virtualization in lxc driver | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Avi Kivity <avi.kivity> |
| Component: | libvirt | Assignee: | Libvirt Maintainers <libvirt-maint> |
| Status: | CLOSED ERRATA | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | unspecified | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 23 | CC: | agedosier, berrange, clalancette, crobinso, dyuan, hhan, itamar, jforbes, laine, libvirt-maint, veillard, virt-maint, xuzhang |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | libvirt-1.2.18.2-3.fc23 | Doc Type: | Bug Fix |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2016-03-22 19:53:14 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: | |||
Thanks for the report Avi, patches posted: https://www.redhat.com/archives/libvir-list/2016-January/msg00928.html Cool, thanks for the quick response. I believe that RHEL suffers from something similar. The patches fix the problem for me. Strangely, the fix works, then stops working:
-bash-4.3$ free
total used free shared buff/cache available
Mem: 9097152 729024 8082584 4512 285544 8082584
Swap: 8167420 0 8167420
-bash-4.3$
-bash-4.3$ free
total used free shared buff/cache available
Mem: 9007199254740991 116 9007199254740875 3972 0 9007199254740875
Swap: 8167420 15348 8152072
-bash-4.3$ cat /proc/meminfo
MemTotal: 9007199254740991 kB
MemFree: 9007199254740875 kB
MemAvailable: 9007199254740875 kB
Buffers: 0 kB
Some time passed between the two free invocations, but the guest was up the whole time (indeed it's the same ssh session). So something fishy is going on/
Hmm. Those patches don't touch the MemTotal/MemFree generation, so probably a pre-existing bug. We pull values from cgroups, so maybe something is getting out of sync I'll use this bug to track backporting the upstream patches. If you hit the other issue again please open a separate bug libvirt-1.2.18.2-3.fc23 has been submitted as an update to Fedora 23. https://bodhi.fedoraproject.org/updates/FEDORA-2016-399269e155 libvirt-1.2.18.2-3.fc23 has been pushed to the Fedora 23 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2016-399269e155 libvirt-1.2.18.2-3.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report. |
Description of problem: /proc/meminfo virtualization has incorrect values, leading applications that depend on it to behave incorrectly. Version-Release number of selected component (if applicable): libvirt-1.2.18.2-1.fc23.x86_64 How reproducible: Always Steps to Reproduce: 1. Run an lxc container with limited memory 2. run 'free' or 'cat /proc/meminfo' Actual results: $ virt-install --connect lxc:/// --name fedora23 --memory 2048 Starting install... Creating domain... | 0 B 00:00:00 Connected to domain fedora23 Escape character is ^] sh-4.3# ls bin dev home lib64 media opt root sbin sys usr boot etc lib lost+found mnt proc run srv tmp var sh-4.3# free total used free shared buff/cache available Mem: 2097152 -1159568 2096076 956936 1160644 20559700 Swap: 10485756 308704 10177052 sh-4.3# cat /proc/meminfo MemTotal: 2097152 kB MemFree: 2096240 kB MemAvailable: 20448244 kB Buffers: 0 kB Cached: 20 kB SwapCached: 12436 kB Active: 652 kB Inactive: 16 kB Active(anon): 648 kB Inactive(anon): 0 kB Active(file): 4 kB Inactive(file): 16 kB Unevictable: 0 kB Mlocked: 24588 kB SwapTotal: 10485756 kB SwapFree: 10177052 kB Dirty: 120 kB Writeback: 0 kB AnonPages: 10714672 kB Mapped: 745532 kB Shmem: 939428 kB Slab: 1160820 kB SReclaimable: 1010288 kB SUnreclaim: 150532 kB KernelStack: 18384 kB PageTables: 113388 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 26906196 kB Committed_AS: 20654132 kB VmallocTotal: 34359738367 kB VmallocUsed: 435904 kB VmallocChunk: 34358947836 kB HardwareCorrupted: 0 kB AnonHugePages: 0 kB HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 2048 kB DirectMap4k: 1329840 kB DirectMap2M: 32116736 kB sh-4.3# Note free's "used" output is negative, and meminfo's MemAvailable is greater than MemTotal and MemFree. Expected results: Something sane Additional info: