CPU affinity with ULE scheduler

[Ivan Voras]

Archimedes Gaviola wrote:
> To Whom It May Concerned:
> 
> Can someone explain or share about ULE scheduler (latest version 2 if
> I'm not mistaken) dealing with CPU affinity? Is there any existing
> benchmarks on this with FreeBSD? Because I am currently using 4BSD

Yes but not for network loads. See for example benchmarks in
http://people.freebsd.org/~kris/scaling/7.0%20and%20beyond.pdf

> scheduler and as what I have observed especially on processing high
> network load traffic on multiple CPU cores, only one CPU were being
> stressed with network interrupt while the rests are mostly in idle
> state. This is an AMD-64 (4x) dual-core IBM system with GigE Broadcom
> network interface cards (bce0 and bce1). Below is the snapshot of the
> case.

This is unfortunately so and cannot be changed for now - you are not the
first with this particular performance problem. BUT, looking at the data
in the snapshot you gave, it's not clear that there is a performance
problem in your case - bce is not nearly taking as much CPU time to be
bottlenecking. What exactly do you think is wrong in your case?

>   PID USERNAME  THR PRI NICE   SIZE    RES STATE  C   TIME   WCPU COMMAND
>    17 root        1 171   52     0K    16K RUN    0  96:04 97.71% idle: cpu0
>    15 root        1 171   52     0K    16K RUN    2  98:41 97.07% idle: cpu2
>    14 root        1 171   52     0K    16K RUN    3 103:56 95.90% idle: cpu3
>    13 root        1 171   52     0K    16K RUN    4 104:17 88.23% idle: cpu4
>    12 root        1 171   52     0K    16K RUN    5  97:59 86.57% idle: cpu5
>    10 root        1 171   52     0K    16K RUN    7  81:51 82.08% idle: cpu7
>    11 root        1 171   52     0K    16K RUN    6  95:28 81.35% idle: cpu6
>    16 root        1 171   52     0K    16K RUN    1 102:15 77.78% idle: cpu1
>    36 root        1 -68 -187     0K    16K WAIT   7  19:37  4.59%
> irq23: bce0 bce1
>    18 root        1 -32 -151     0K    16K CPU0   0   2:13  0.00%
> swi4: clock sio
>  4488 root        1  96    0 30728K  4292K select 3   1:51  0.00% sshd
>    43 root        1 171   52     0K    16K pgzero 3   1:08  0.00% pagezero
>   218 root        1  96    0  3852K  1380K select 3   0:38  0.00% syslogd
>    20 root        1 -44 -163     0K    16K WAIT   7   0:32  0.00% swi1: net


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