Xorg often taking a lot of CPU, whole system slow

[Dotan Cohen]

Often, my Kubuntu 9.10 system slows to a crawl. When this happens,
Xorg is usually the culprit:

top - 10:51:32 up  2:03,  2 users,  load average: 0.72, 0.49, 0.29
Tasks: 168 total,   2 running, 166 sleeping,   0 stopped,   0 zombie
Cpu(s): 31.1%us,  7.9%sy,  0.0%ni, 61.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:   2060628k total,  1631280k used,   429348k free,     1132k buffers
Swap:  2931852k total,        0k used,  2931852k free,   692632k cached

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
 1206 root      20   0  526m 157m  19m S   45  7.8  26:22.25 Xorg
 1756 dotancoh  20   0  472m 240m  24m S   18 11.9  29:01.06 firefox
 1632 dotancoh  20   0  244m  28m  20m S    7  1.4   8:59.91 kwin


What is Xorg doing? How can I diagnose this? Thanks!

-- 
Dotan Cohen

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