Suggestions needed to debug why ps -ef gets stuck

Issue beginning - Few of my PID consume 100% cpu, I want to understand which script is executing that PID command.

My debugging steps:

strace ps -ef

open("/proc/PID/status", O_RDONLY) = 6 read(6, "Name:\textract\nState:\tR (running)"..., 1023) = 1023 close(6) = 0 open("/proc/PID/cmdline", O_RDONLY) = 6 read(6,

So it gets stuck trying to open /proc/PID/cmdline

I tried catting that, it got stuck again

Something is obviously screwed in the kernel, please let me know your suggestions or next debugging steps

Notes: shutdown doesn't work, if I shutdown manually the problem starts again.

ps: Because of my reputation, I am unable to chat. Please feel free to ask output of any suggested commands, I will paste it ASAP!

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Does iotop give any unusual pointers? –  Jonathan Ross Apr 9 '11 at 19:08
I don't have iotop. –  72616b657368 Apr 9 '11 at 19:12
Is this a real server or a OpenVZ / Virtuozzo container? –  Matthew Ife Apr 9 '11 at 19:28
Can you install other tools? –  Jonathan Ross Apr 9 '11 at 19:52
It's a baremetal one –  72616b657368 Apr 9 '11 at 19:52

If your system has a root kit, the ps or even /proc could be corrupted due to a bug in the root kit. I'm not real sure how you get out from under a root kit without a reinstall.

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