events/0 thread in kernels 2.6.22*fc6 causing scheduling latency

[Mike Fleetwood]

Hi,

Since I upgraded my FC6 box from kernel-2.6.20-1.2962.fc6 to
kernel-2.6.22.1-32.fc6, and now 2.6.22.2-42.fc6, I am getting pauses
from the whole OS.  They last ~1 second and occur every few minutes.
Every application becomes unresponsive for the duration.  The 1 second
scheduler latency this causes is long enough for my music player to be
effected and the audio track to be interrupted.  This makes the fault
very easy to hear.  At the same time kernel thread events/0 seems to
use all the CPU time.  Here is the first few lines of top's output
when a pause happens:
 top - 21:39:41 up  1:17,  2 users,  load average: 1.05, 1.20, 1.24
 Tasks: 138 total,   4 running, 134 sleeping,   0 stopped,   0 zombie
 Cpu(s):  2.3%us, 29.3%sy, 68.4%ni,  0.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
 Mem:   2074880k total,  1355244k used,   719636k free,    62144k buffers
 Swap:  1004052k total,        0k used,  1004052k free,   882684k cached

   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
  5525 mike      39  19  202m  81m 4016 R 68.4  4.0  13:07.46 hadcm3transum_5
     6 root      15  -5     0    0    0 S 28.5  0.0   0:53.40 events/0
  3619 mike      20   0 45620 8264 5856 S  0.9  0.4   0:18.58 xmms
  3318 root      20   0  328m  46m 8132 S  0.6  2.3   1:39.60 Xorg
  3524 mike      20   0 76728  23m 9640 S  0.6  1.2   1:13.15 bittorrent
  3557 mike      20   0  211m 115m  30m S  0.6  5.7   3:54.24 firefox-bin
  3489 mike      20   0 57240  23m  15m S  0.3  1.1   0:04.02 gnome-terminal
  5583 root      20   0  2204 1100  832 R  0.3  0.1   0:01.14 top
28.5% CPU time used by events/0 of a single 3 second top refresh is
0.85 seconds of CPU time.  Rebooting back to kernel 2.6.20 completely
fixes it.

Has any one else seen this issue?
Does anyone know what kernel thread events/0 does?
Could this be related to CFS newly introduced into Fedora's kernel 2.6.22?
Can anybody suggest how to fix this issue?

Thanks,
Mike