1#!/bin/sh
2
3# Read a line coming from `./aggregate.perl --sort-by regression ...`
4# and automatically bisect to find the commit responsible for the
5# performance regression.
6#
7# Lines from `./aggregate.perl --sort-by regression ...` look like:
8#
9# +100.0% p7821-grep-engines-fixed.1 0.04(0.10+0.03) 0.08(0.11+0.08) v2.14.3 v2.15.1
10# +33.3% p7820-grep-engines.1 0.03(0.08+0.02) 0.04(0.08+0.02) v2.14.3 v2.15.1
11#
12
13die () {
14 echo >&2 "error: $*"
15 exit 1
16}
17
18while [ $# -gt 0 ]; do
19 arg="$1"
20 case "$arg" in
21 --help)
22 echo "usage: $0 [--config file] [--subsection subsection]"
23 exit 0
24 ;;
25 --config)
26 shift
27 GIT_PERF_CONFIG_FILE=$(cd "$(dirname "$1")"; pwd)/$(basename "$1")
28 export GIT_PERF_CONFIG_FILE
29 shift ;;
30 --subsection)
31 shift
32 GIT_PERF_SUBSECTION="$1"
33 export GIT_PERF_SUBSECTION
34 shift ;;
35 --*)
36 die "unrecognised option: '$arg'" ;;
37 *)
38 die "unknown argument '$arg'"
39 ;;
40 esac
41done
42
43read -r regression subtest oldtime newtime oldrev newrev
44
45test_script=$(echo "$subtest" | sed -e 's/\(.*\)\.[0-9]*$/\1.sh/')
46test_number=$(echo "$subtest" | sed -e 's/.*\.\([0-9]*\)$/\1/')
47
48# oldtime and newtime are decimal number, not integers
49
50oldtime=$(echo "$oldtime" | sed -e 's/^\([0-9]\+\.[0-9]\+\).*$/\1/')
51newtime=$(echo "$newtime" | sed -e 's/^\([0-9]\+\.[0-9]\+\).*$/\1/')
52
53test $(echo "$newtime" "$oldtime" | awk '{ print ($1 > $2) }') = 1 ||
54 die "New time '$newtime' shoud be greater than old time '$oldtime'"
55
56tmpdir=$(mktemp -d -t bisect_regression_XXXXXX) || die "Failed to create temp directory"
57echo "$oldtime" >"$tmpdir/oldtime" || die "Failed to write to '$tmpdir/oldtime'"
58echo "$newtime" >"$tmpdir/newtime" || die "Failed to write to '$tmpdir/newtime'"
59
60# Bisecting must be performed from the top level directory (even with --no-checkout)
61(
62 toplevel_dir=$(git rev-parse --show-toplevel) || die "Failed to find top level directory"
63 cd "$toplevel_dir" || die "Failed to cd into top level directory '$toplevel_dir'"
64
65 git bisect start --no-checkout "$newrev" "$oldrev" || die "Failed to start bisecting"
66
67 git bisect run t/perf/bisect_run_script "$test_script" "$test_number" "$tmpdir"
68 res="$?"
69
70 git bisect reset
71
72 exit "$res"
73)