CPU affinity with ULE scheduler

[Archimedes Gaviola]

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
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.

  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


Thanks,
Archimedes