Re: Multiqueue CPU load excessive on two cores, R8...

Kaspars_Zibarts · ‎2020-09-17

Hi! Has anyone played more with the new MQ in 3.10 kernel - we seem to have rather uneven load distribution between cores

Not too sure if it's number 24 (that's allocated for MQ) that's not really power of 2 i.e. 16 or 32) that could make a difference

you can also see that busy CPUs changed after failover

Nothing else points to these cores, just MQ

Timothy_Hall · ‎2020-09-18

Hmm, try running mq_mng –o –vv for more verbose output. Sounds kind of similar to this issue that Check Point is looking at:

https://community.checkpoint.com/t5/VSX/R80-40-High-CPU-usage-on-snd-cores/m-p/95905#M1041

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Kaspars_Zibarts · ‎2020-09-20

Great thanks Timothy! @Ilya_Yusupov - do you think you could cast your eye over MQ issues we are having?

I have actually changed MQ allocation to have 16 cores for 40Gbps interfaces and 8 cores for 10Gbps (instead of all sharing 24)

But the result is the same for 40Gbps - I have 3 interfaces taking considerably higher load

 mq_mng --show -vvv
Total 72 cores. Multiqueue 24 cores: 0,36,1,37,2,38,3,39,4,40,5,41,6,42,7,43,8,44,9,45,10,46,11,47
i/f             type            state           mode            cores
------------------------------------------------------------------------------------------------
Mgmt            igb             Up              Auto (2)*       0(235),0(1205)
eth2-01         i40e            Up              Manual (8)      9(878),10(879),11(880),44(881)
                                                                ,45(882),46(883),47(884),8(885
                                                                )
eth2-02         i40e            Up              Manual (8)      9(960),10(961),11(962),44(963)
                                                                ,45(964),46(965),47(966),8(967
                                                                )
eth3-01         i40e            Up              Manual (8)      9(533),10(534),11(535),44(536)
                                                                ,45(537),46(538),47(539),8(540
                                                                )
eth4-04         i40e            Up              Manual (8)      9(384),10(385),11(386),44(387)
                                                                ,45(388),46(389),47(390),8(391
                                                                )
eth5-01         mlx5_core       Up              Manual (16)     3(322),4(323),5(324),6(325),7(
                                                                326),36(327),37(328),38(329),3
                                                                9(330),40(331),41(332),42(333)
                                                                ,43(334),0(335),1(336),2(337)
eth5-02         mlx5_core       Up              Manual (16)     3(472),4(473),5(474),6(475),7(
                                                                476),36(477),37(478),38(479),3
                                                                9(480),40(481),41(482),42(483)
                                                                ,43(484),0(485),1(486),2(487)
* Management interface
------------------------------------------------------------------------------------------------
Mgmt <igb> max 8 cur 2
5e:00.0 Ethernet controller: Intel Corporation I350 Gigabit Network Connection (rev 01)
------------------------------------------------------------------------------------------------
eth2-01 <i40e> max 72 cur 8
af:00.0 Ethernet controller: Intel Corporation Ethernet Controller X710 for 10GbE SFP+ (rev 02)
------------------------------------------------------------------------------------------------
eth2-02 <i40e> max 72 cur 8
af:00.1 Ethernet controller: Intel Corporation Ethernet Controller X710 for 10GbE SFP+ (rev 02)
------------------------------------------------------------------------------------------------
eth3-01 <i40e> max 72 cur 8
3c:00.0 Ethernet controller: Intel Corporation Ethernet Controller X710 for 10GbE SFP+ (rev 02)
------------------------------------------------------------------------------------------------
eth4-04 <i40e> max 72 cur 8
3b:00.3 Ethernet controller: Intel Corporation Ethernet Controller X710 for 10GbE SFP+ (rev 02)
------------------------------------------------------------------------------------------------
eth5-01 <mlx5_core> max 60 cur 16
86:00.0 Ethernet controller: Mellanox Technologies MT27700 Family [ConnectX-4]
------------------------------------------------------------------------------------------------
eth5-02 <mlx5_core> max 60 cur 16
86:00.1 Ethernet controller: Mellanox Technologies MT27700 Family [ConnectX-4]

core            interfaces      queue                     irq        rx packets      tx packets
------------------------------------------------------------------------------------------------
0               eth5-01         eth5-01-13                335        14350733832     14275579034
                eth5-02         eth5-02-13                485        14466343063     17243631242
                Mgmt            Mgmt-TxRx-0               235        78534394        64112480
                                Mgmt-TxRx-1               1205       67134729        459077031
1               eth5-01         eth5-01-14                336        18381027498     16258562430
                eth5-02         eth5-02-14                486        17465071873     15859764318
2               eth5-01         eth5-01-15                337        15268826290     14474595992
                eth5-02         eth5-02-15                487        14332288014     47882368284
3               eth5-01         eth5-01-0                 322        16870013293     16103167502
                eth5-02         eth5-02-0                 472        18391705437     16770347908
4               eth5-01         eth5-01-1                 323        18341870980     42982282750
                eth5-02         eth5-02-1                 473        53056458377     18790530142
5               eth5-01         eth5-01-2                 324        18092841969     15479879244
                eth5-02         eth5-02-2                 474        17678594518     17759340911
6               eth5-01         eth5-01-3                 325        18569966356     17374626959
                eth5-02         eth5-02-3                 475        19207199286     16473895178
7               eth5-01         eth5-01-4                 326        16371197169     55042906070
                eth5-02         eth5-02-4                 476        17966599526     16614132655
8               eth2-01         i40e-eth2-01-TxRx-7       885        3741853166      2042916585
                eth2-02         i40e-eth2-02-TxRx-7       967        791080580       1834917140
                eth4-04         i40e-eth4-04-TxRx-7       391        18              82
                eth3-01         i40e-eth3-01-TxRx-7       540        1978429151      2062247563
9               eth2-01         i40e-eth2-01-TxRx-0       878        4125404939      2312180264
                eth2-02         i40e-eth2-02-TxRx-0       960        923577271       2950661062
                eth4-04         i40e-eth4-04-TxRx-0       384        0               163
                eth3-01         i40e-eth3-01-TxRx-0       533        2039654091      1910504944
10              eth2-01         i40e-eth2-01-TxRx-1       879        3708196131      1858716440
                eth2-02         i40e-eth2-02-TxRx-1       961        723852572       2140074966
                eth4-04         i40e-eth4-04-TxRx-1       385        0               21
                eth3-01         i40e-eth3-01-TxRx-1       534        1767080577      2109527000
11              eth2-01         i40e-eth2-01-TxRx-2       880        3415244805      1952244111
                eth2-02         i40e-eth2-02-TxRx-2       962        743700658       1828484239
                eth4-04         i40e-eth4-04-TxRx-2       386        0               173
                eth3-01         i40e-eth3-01-TxRx-2       535        2094555319      2140296068
36              eth5-01         eth5-01-5                 327        16564644126     19758585623
                eth5-02         eth5-02-5                 477        16177811733     17520582730
37              eth5-01         eth5-01-6                 328        31472538636     16944805026
                eth5-02         eth5-02-6                 478        25255422251     21348269114
38              eth5-01         eth5-01-7                 329        15736296142     16989047395
                eth5-02         eth5-02-7                 479        17850328811     17267073118
39              eth5-01         eth5-01-8                 330        14548417778     17227449231
                eth5-02         eth5-02-8                 480        17253608323     15922302163
40              eth5-01         eth5-01-9                 331        17246160429     31679890308
                eth5-02         eth5-02-9                 481        46504867542     24976635307
41              eth5-01         eth5-01-10                332        14887319564     16507515513
                eth5-02         eth5-02-10                482        15862234756     17366704751
42              eth5-01         eth5-01-11                333        18121039578     16932088569
                eth5-02         eth5-02-11                483        14088983186     14722704253
43              eth5-01         eth5-01-12                334        36432500242     48388767915
                eth5-02         eth5-02-12                484        26046626514     16665977419
44              eth2-01         i40e-eth2-01-TxRx-3       881        3719372336      2047174513
                eth2-02         i40e-eth2-02-TxRx-3       963        768559972       2026740212
                eth4-04         i40e-eth4-04-TxRx-3       387        0               24
                eth3-01         i40e-eth3-01-TxRx-3       536        2003820593      1920066858
45              eth2-01         i40e-eth2-01-TxRx-4       882        3478124337      2217071136
                eth2-02         i40e-eth2-02-TxRx-4       964        835661452       1880955919
                eth4-04         i40e-eth4-04-TxRx-4       388        0               18
                eth3-01         i40e-eth3-01-TxRx-4       537        1939612139      2095272331
46              eth2-01         i40e-eth2-01-TxRx-5       883        3146040696      1984205490
                eth2-02         i40e-eth2-02-TxRx-5       965        878741983       1986164797
                eth4-04         i40e-eth4-04-TxRx-5       389        187164163       18
                eth3-01         i40e-eth3-01-TxRx-5       538        1663650364      2043452656
47              eth2-01         i40e-eth2-01-TxRx-6       884        3657784843      1765152235
                eth2-02         i40e-eth2-02-TxRx-6       966        824913871       2045747277
                eth4-04         i40e-eth4-04-TxRx-6       390        0               541744470
                eth3-01         i40e-eth3-01-TxRx-6       539        1773453351      1789497778

Henrik_Noerr1 · ‎2020-09-21

hmm interesting - we are on the verge of introducing NICs using the i40e driver. Notice the latest EA jumbo:

NEW: The i40e driver version was upgraded to improve performance.

Fix is relevant for Gaia 3.10 only.

"... Error I40E_AQ_RC_EINVAL adding RX filters on PF..." error may appear during i40e driver operation and RSS key may be reset during certain driver operations.

Fix is relevant for Gaia 3.10 only.

/Henrik

Kaspars_Zibarts · ‎2020-09-21

were using mellanox drivers on 40Gbps ports (eth5-0x) in logs above

Kaspars_Zibarts · ‎2020-09-22

Confirmed - it's a bug and requires to port a fix onto R80.30. just be aware if you're using 40Gbps+ interfaces and 3.10 kernel.

Thanks @Ilya_Yusupov for direct support!

Kaspars_Zibarts · ‎2021-06-16

Just a quick update on the topic of Mellanox (40G interfaces) driver load distribution.

Worked with R&D for nearly 9 months and still did not get to the bottom of it and last solution was trying upgrading to R80.40 which is currently pending.

BUT. We worked out ourselves that it was traffic to one specific NFS (port 2049) server that caused this! We had 7 or 8 different clients in the same subnet sending insane amount of logs in plain text format generating approx 6Gbps traffic. And for some reason Mellanox driver hash decided to loadshare all of it mostly to a single core (39 in screenshot below) plus one more (2). Which leads me to think that there's something fishy with hash algorithm:

Here's list of connections that were "removed"

Thought it it's worthwhile sharing in case someone else is struggling with the same MQ CPU load distribution challenges

Are you a member of CheckMates?

Multiqueue CPU load excessive on two cores, R80.30 T215 3.10