strace all apache child processes

# ps h --ppid `cat /var/run/` -o pid | awk '{print "-v -ff -tt -T -s 1024 -o /tmp/strace.out -p " $1}' | xargs strace

This will attach strace to each of the apache child processes.

-v verbose
-ff with -o will log the output to "/tmp/strace.out.{pid}" and follow forks.
-tt prints the timestamp of each call.
-T prints the duration of each call.
-s specifies the maximum size of the output string to more than the default 32.

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