Bug 1734316
| Summary: | multifd migration does not honour speed limits, consumes entire bandwidth of NIC | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux Advanced Virtualization | Reporter: | Daniel Berrangé <berrange> |
| Component: | qemu-kvm | Assignee: | Juan Quintela <quintela> |
| Status: | CLOSED ERRATA | QA Contact: | Li Xiaohui <xiaohli> |
| Severity: | unspecified | Docs Contact: | |
| Priority: | medium | ||
| Version: | 8.0 | CC: | chayang, ddepaula, fjin, hhuang, jinzhao, juzhang, knoel, virt-maint, xiaohli |
| Target Milestone: | rc | Flags: | hhuang:
mirror+
|
| Target Release: | 8.0 | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | qemu-kvm-4.1.0-9.module+el8.1.0+4210+23b2046a | Doc Type: | If docs needed, set a value |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2019-11-06 07:18:12 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: | |||
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Description
Daniel Berrangé
2019-07-30 08:50:52 UTC
THere is a patch upstream for this. Adding it to the queue. I can reproduce this issue on host(kernel-4.18.0-125.el8.x86_64 & qemu-4.1.0-rc3).
(qemu) info migrate
globals:
...
capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off events: off postcopy-ram: off x-colo: off release-ram: off block: off return-path: off pause-before-switchover: off multifd: on dirty-bitmaps: off postcopy-blocktime: off late-block-activate: off x-ignore-shared: off
Migration status: completed
total time: 1432 milliseconds
downtime: 258 milliseconds
setup: 41 milliseconds
transferred ram: 2650508 kbytes
throughput: 15611.23 mbps ----> about 2GBps > 100MBps
remaining ram: 0 kbytes
total ram: 8405832 kbytes
duplicate: 1471276 pages
skipped: 0 pages
normal: 657703 pages
normal bytes: 2630812 kbytes
dirty sync count: 4
page size: 4 kbytes
multifd bytes: 2637576 kbytes
pages-per-second: 827188
(qemu) info migrate_parameters
...
max-bandwidth: 104857600 bytes/second
downtime-limit: 300 milliseconds
x-checkpoint-delay: 20000
block-incremental: off
multifd-channels: 2
xbzrle-cache-size: 67108864
max-postcopy-bandwidth: 0
tls-authz: '(null)'
And not consume entire bandwidth of NIC: 40Gbps(5GBps) [root@dell-per430-10 work]# ethtool enp4s0f1 Settings for enp4s0f1: Supported ports: [ FIBRE ] Supported link modes: 40000baseCR4/Full Supported pause frame use: Symmetric Supports auto-negotiation: Yes Supported FEC modes: Not reported Advertised link modes: 40000baseCR4/Full Advertised pause frame use: No Advertised auto-negotiation: Yes Advertised FEC modes: Not reported Speed: 40000Mb/s Duplex: Full Port: Direct Attach Copper PHYAD: 0 Transceiver: internal Auto-negotiation: on Supports Wake-on: d Wake-on: d Current message level: 0x00000007 (7) drv probe link Link detected: yes upstream commit 1b81c974ccfd536aceef840e220912b142a7dda0 brew: 23335260 We need QA_ACK, please. test this bz via case RHEL-174630 on environment[1], the result is right: environment[1]: src&dst host info: kernel-4.18.0-144.el8.x86_64 & qemu-img-4.1.0-10.module+el8.1.0+4234+33aa4f57.x86_64 guest info: kernel-4.18.0-141.el8.x86_64 the important test steps and results: (qemu) migrate_set_speed 50M (qemu) info migrate_parameters ... max-bandwidth: 52428800 bytes/second (qemu) migrate -d tcp:192.168.11.21:5555 (qemu) info migrate ... capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off events: off postcopy-ram: off x-colo: off release-ram: off return-path: off pause-before-switchover: off multifd: on dirty-bitmaps: off postcopy-blocktime: off late-block-activate: off x-ignore-shared: off Migration status: active total time: 1440 milliseconds expected downtime: 300 milliseconds setup: 41 milliseconds transferred ram: 77809 kbytes throughput: 420.72 mbps ... (qemu) migrate_set_speed 200M (qemu) info migrate_parameters ... max-bandwidth: 209715200 bytes/second (qemu) info migrate ... capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off events: off postcopy-ram: off x-colo: off release-ram: off return-path: off pause-before-switchover: off multifd: on dirty-bitmaps: off postcopy-blocktime: off late-block-activate: off x-ignore-shared: off Migration status: active total time: 18736 milliseconds expected downtime: 300 milliseconds setup: 41 milliseconds transferred ram: 1099571 kbytes throughput: 1682.66 mbps ... According to above result, set this bz verified, thanks Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2019:3723 |