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Plotting the sleep/wait chain of a process

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http://unix.stackexchange.com – I often want to know why a process in the middle of a pipeline is sleeping and not busy processing data. My current method is: find the pid of interest sudo strace -pt pid to get the blocking syscall and object (fd, child, futex, etc.) hit ctrl+c to detach strace look up the appropriate object in /proc/pid grep /proc/ or use lsof to find the other end of the pipe or process being waited on repeat from #1 with the new pid This is a pretty slow process that combines a lot of tools that don't play well together (strace in particular is hard to automate). Is there a tool that will do this l (HowTos)

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Submitted by Songlist on 09/05/2012

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piping strace to grep 39 weeks 5 days ago

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Is there something special about strace that causes this behavior?

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Published at LXer:

Having trouble figuring out why Apache isn't starting, or another program is crashing and burning, and the logfiles are giving no clue? Time to reach for strace. What's strace? The strace utility is used to run a command and display its system calls, so you can see exactly what the program is doing until it exits.

I am aware about the powerful /proc file system. If I have a process id, I can easily see the details about it by browsing the /proc/<process-id>/. Consider I have a process that starts, does some job and ends. Something like "grep" or "find". How do you see the details of this process?

progandy wrote:felixonmars wrote:I've tried strace -f -eopen, but it shows that file was not opened during installation of xplc, but did exist after then.You traced the wrong system call: sudo strace -f -esymlink pacman -S xplcOops, thanks a lot.I finally know that it is ldconfig which creates the symlink, by using:# strace -f -e trace=file,process pacman -S xplc

felixonmars https://

Detailed Per-Process Profiling 47 weeks 12 hours ago

I am looking for a way to profile a single process including time spent for CPU, I/O, system calls and optionally memory usage over time.

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I know several IO