poormansprofiler, but with some ocaml specific extensions

poorcamelsprofiler

#!/bin/bash

set -e -u

nsamples=20

sleeptime=0.1

if [[ $# -ne 1 && $# -ne 2 ]]; then
    cat <<EOF
Usage:
$0 PROG_NAME
$0 --mem PROG_NAME

where PROG_NAME is given to pgrep. Note that long program names may be
truncated in the process list; you can do 'pgrep -l SUB' (for some
substring of the program name) to see what it's truncated to, and use
that as PROG_NAME.
EOF
    exit 1
fi

if [[ $1 = -m || $1 = --mem ]]; then
    shift
    # https://sympa.inria.fr/sympa/arc/caml-list/2011-08/msg00050.html
    cmd () {
        sudo gdb -ex "b caml_call_gc" -ex "c" -ex "bt" "$@"
    }
else
    cmd () {
        sudo gdb -ex "set pagination 0" -ex "thread apply all bt" "$@"
    }
fi

prog=$1
pid () { pgrep --newest "${prog}"; }

# avoid the "No such file" from gdb by adding this:
#ocamlsrc=' -d "$(opam config var lib)/ocaml"'

for x in $(seq 1 "${nsamples}"); do
    cmd -p "$(pid)" -batch -n -q
    sleep "${sleeptime}"
done | awk '
  BEGIN { s = ""; prev = "" }
  /^(Thread|Breakpoint)/ { if(s) print s; s = ""; prev = "" }
  /^\#/ && $4 != prev { prev = $4; if (s != "" ) { s = s "," $4} else { s = $4 } }
  END { print s }' | sort | uniq -c | sort -r -n -k 1,1

# Like http://poormansprofiler.org/ but collapse same-names (so much recursion in ocaml)

# TODO: grep out malloc.c stuff
# http://stackoverflow.com/questions/9220853/call-to-malloc-failing-in-gdb-session