Bug 857577
| Summary: | Improved live migration statistics | |||
|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | Karen Noel <knoel> | |
| Component: | qemu-kvm | Assignee: | Juan Quintela <quintela> | |
| Status: | CLOSED CURRENTRELEASE | QA Contact: | Virtualization Bugs <virt-bugs> | |
| Severity: | unspecified | Docs Contact: | ||
| Priority: | unspecified | |||
| Version: | 7.0 | CC: | ctatman, jdenemar, juzhang, knoel, michen, qzhang, shu, virt-maint | |
| Target Milestone: | rc | Keywords: | FutureFeature | |
| Target Release: | 7.0 | |||
| Hardware: | Unspecified | |||
| OS: | Unspecified | |||
| Whiteboard: | ||||
| Fixed In Version: | QEMU 1.3 | Doc Type: | Release Note | |
| Doc Text: |
Improved Live Migration Statistics
Information about live migration is now available to analyze and tune performance. Improved statistics include information about expected downtime, downtime or dirty pages rate.
|
Story Points: | --- | |
| Clone Of: | ||||
| : | 857578 (view as bug list) | Environment: | ||
| Last Closed: | 2014-06-13 10:19:00 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: | ||||
| Bug Depends On: | ||||
| Bug Blocks: | 801536, 857578, 918410, 1061570, 1063486 | |||
|
Description
Karen Noel
2012-09-14 22:39:33 UTC
[Qemu-devel] [PULL v3 00/41] Migration cleanups, refactorings, stats, and more http://marc.info/?l=qemu-devel&m=135049188317185&w=2 - It introduces the stats discused previously * expected_downtime * downtime * dirty_pages_rate This bug could be verified on qemu-kvm-rhev-1.5.3-31.el7.x86_64.
1. Migrate guest with the default configuration:
(qemu) info migrate
capabilities: xbzrle: off x-rdma-pin-all: off auto-converge: off zero-blocks: off
Migration status: active
total time: 17943 milliseconds
expected downtime: 30 milliseconds ==> Default downtime is correct.
setup: 149 milliseconds
transferred ram: 579095 kbytes
throughput: 268.57 mbps ==> Match to the default migration speed 30MBps
remaining ram: 112640 kbytes
total ram: 4325856 kbytes
duplicate: 910810 pages
skipped: 0 pages
normal: 142494 pages
normal bytes: 569976 kbytes
(qemu) info migrate
capabilities: xbzrle: off x-rdma-pin-all: off auto-converge: off zero-blocks: off
Migration status: completed
total time: 20572 milliseconds
downtime: 209 milliseconds
setup: 149 milliseconds
transferred ram: 660591 kbytes
throughput: 268.58 mbps
remaining ram: 0 kbytes
total ram: 4325856 kbytes
duplicate: 933137 pages
skipped: 0 pages
normal: 162779 pages
normal bytes: 651116 kbytes
Above values are updated during and after migration.
2. Set "downtime" to 1s, "migration speed" to 100MBps:
(qemu) info migrate
capabilities: xbzrle: off x-rdma-pin-all: off auto-converge: off zero-blocks: off
Migration status: active
total time: 4634 milliseconds
expected downtime: 1000 milliseconds ==> Correct
setup: 59 milliseconds
transferred ram: 431412 kbytes
throughput: 830.57 mbps ==> Correct
remaining ram: 279236 kbytes
total ram: 4325856 kbytes
duplicate: 905999 pages
skipped: 0 pages
normal: 105656 pages
normal bytes: 422624 kbytes
(qemu) info migrate
capabilities: xbzrle: off x-rdma-pin-all: off auto-converge: off zero-blocks: off
Migration status: completed
total time: 6530 milliseconds
downtime: 258 milliseconds
setup: 59 milliseconds
transferred ram: 620975 kbytes
throughput: 830.88 mbps
remaining ram: 0 kbytes
total ram: 4325856 kbytes
duplicate: 935300 pages
skipped: 0 pages
normal: 152890 pages
normal bytes: 611560 kbytes
After migration, check the above values are reasonable.
3. Turn on "xbzrle","auto-converge", "x-rdma-pin-all".
(qemu) info migrate
capabilities: xbzrle: on x-rdma-pin-all: on auto-converge: on zero-blocks: off
Migration status: completed
total time: 19714 milliseconds
downtime: 205 milliseconds
setup: 54 milliseconds
transferred ram: 631236 kbytes
throughput: 268.57 mbps
remaining ram: 0 kbytes
total ram: 4325856 kbytes
duplicate: 936059 pages
skipped: 0 pages
normal: 155447 pages
normal bytes: 621788 kbytes
cache size: 67108864 bytes
xbzrle transferred: 5 kbytes
xbzrle pages: 90 pages
xbzrle cache miss: 5942
xbzrle overflow : 0
4. Test with qmp:
(1) default configuration:
{"execute":"query-migrate"}
{"return": {"expected-downtime": 30, "status": "active", "setup-time": 56, "total-time": 4867, "ram": {"total": 4429676544, "remaining": 4254449664, "mbps": 268.5668, "transferred": 164508924, "duplicate": 2701, "dirty-pages-rate": 0, "skipped": 0, "normal-bytes": 164163584, "normal": 40079}}
After migration finished:
{"return": {"status": "completed", "setup-time": 56, "downtime": 215, "total-time": 23002, "ram": {"total": 4429676544, "remaining": 0, "mbps": 268.5704, "transferred": 758725202, "duplicate": 905178, "dirty-pages-rate": 0, "skipped": 0, "normal-bytes": 749113344, "normal": 182889}}}
(2) with xbzrle:
{"return": {"xbzrle-cache": {"bytes": 660, "cache-size": 67108864, "pages": 21, "overflow": 0, "cache-miss": 2992}, "status": "completed", "setup-time": 57, "downtime": 211, "total-time": 23001, "ram": {"total": 4429676544, "remaining": 0, "mbps": 268.56968, "transferred": 757441588, "duplicate": 905213, "dirty-pages-rate": 0, "skipped": 0, "normal-bytes": 747831296, "normal": 182576}}}
So, the live migration statistics are included in the current qemu-kvm, this bug is fixed.
This request was resolved in Red Hat Enterprise Linux 7.0. Contact your manager or support representative in case you have further questions about the request. |