> Jan Varga <varga@frru.utcru.sk> wonders:
> > Hi,
> >
> > sometimes I notice that some processes starts consume much CPU time
> > but when I run 'strace -p pid' nothing happens
> > It is usualy netscape or some kde applications
>
> A process which is doing something purely in user space
> without doing syscalls will not appear doing anything in
> 'strace' sense -- which is to track kernel calls.
>
> Use 'gdb' to figure out where the beast is spinning.
> (If debug symbols are available.)
>
Even better, use the "ltrace" command. It's like strace, but for library
calls, and it doesn't need debug symbols. The web page is at
http://www.debian.org/Packages/unstable/utils/ltrace.html
Example: I ltrace my netscape:
$ ltrace -p 1397
XFindContext(0x0880c800, 0x089aca00, -1, 0xbfffe480, 3) = 0
XtGetSubvalues(0x089ad500, 0x08812800, 21, 0x08b3bca0, 1 <unfinished ...>
ffs(0x80000000, 88, 21, 0x08726a78, 7 <unfinished ...>
--- SIGALRM (Alarm clock) ---
gettimeofday(0xbfffe28c, 0, 0x084d94c8, 0x4029acc0, 0) = 0
__errno_location() = 0x4029acc0
breakpointed at 0x08136253 (?)
ffs(0x80000000, 88, 21, 0x08726a78, 7) = 32
XrmStringToQuark(0x08751ed8, 0x08750e28, 0xbfffe4d4, 0x08726a78,
0x08795180) = 7471
Brad
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