t/perf: add scripts to bisect performance regressions

The new bisect_regression script can be used to automatically bisect performance regressions. It will pass the new bisect_run_script to `git bisect run`. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Christian Couder committed Apr 8, 2018 at 11:35 UTC 297e685cbaaa0d33125dc59ce2aa55f03a836598
2 files changed +120
t/perf/bisect_regression new
+73
@@ -0,0 +1,73 @@
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 +
13 +die () {
14 + echo >&2 "error: $*"
15 + exit 1
16 +}
17 +
18 +while [ $# -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 '$arg'"
39 + ;;
40 + esac
41 +done
42 +
43 +read -r regression subtest oldtime newtime oldrev newrev
44 +
45 +test_script=$(echo "$subtest" | sed -e 's/\(.*\)\.[0-9]*$/\1.sh/')
46 +test_number=$(echo "$subtest" | sed -e 's/.*\.\([0-9]*\)$/\1/')
47 +
48 +# oldtime and newtime are decimal number, not integers
49 +
50 +oldtime=$(echo "$oldtime" | sed -e 's/^\([0-9]\+\.[0-9]\+\).*$/\1/')
51 +newtime=$(echo "$newtime" | sed -e 's/^\([0-9]\+\.[0-9]\+\).*$/\1/')
52 +
53 +test $(echo "$newtime" "$oldtime" | awk '{ print ($1 > $2) }') = 1 ||
54 + die "New time '$newtime' shoud be greater than old time '$oldtime'"
55 +
56 +tmpdir=$(mktemp -d -t bisect_regression_XXXXXX) || die "Failed to create temp directory"
57 +echo "$oldtime" >"$tmpdir/oldtime" || die "Failed to write to '$tmpdir/oldtime'"
58 +echo "$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 +)
t/perf/bisect_run_script new
+47
@@ -0,0 +1,47 @@
1 +#!/bin/sh
2 +
3 +script="$1"
4 +test_number="$2"
5 +info_dir="$3"
6 +
7 +# This aborts the bisection immediately
8 +die () {
9 + echo >&2 "error: $*"
10 + exit 255
11 +}
12 +
13 +bisect_head=$(git rev-parse --verify BISECT_HEAD) || die "Failed to find BISECT_HEAD ref"
14 +
15 +script_number=$(echo "$script" | sed -e "s/^p\([0-9]*\).*\$/\1/") || die "Failed to get script number for '$script'"
16 +
17 +oldtime=$(cat "$info_dir/oldtime") || die "Failed to access '$info_dir/oldtime'"
18 +newtime=$(cat "$info_dir/newtime") || die "Failed to access '$info_dir/newtime'"
19 +
20 +cd t/perf || die "Failed to cd into 't/perf'"
21 +
22 +result_file="$info_dir/perf_${script_number}_${bisect_head}_results.txt"
23 +
24 +GIT_PERF_DIRS_OR_REVS="$bisect_head"
25 +export GIT_PERF_DIRS_OR_REVS
26 +
27 +./run "$script" >"$result_file" 2>&1 || die "Failed to run perf test '$script'"
28 +
29 +rtime=$(sed -n "s/^$script_number\.$test_number:.*\([0-9]\+\.[0-9]\+\)(.*).*\$/\1/p" "$result_file")
30 +
31 +echo "newtime: $newtime"
32 +echo "rtime: $rtime"
33 +echo "oldtime: $oldtime"
34 +
35 +# Compare ($newtime - $rtime) with ($rtime - $oldtime)
36 +# Times are decimal number, not integers
37 +
38 +if test $(echo "$newtime" "$rtime" "$oldtime" | awk '{ print ($1 - $2 > $2 - $3) }') = 1
39 +then
40 + # Current commit is considered "good/old"
41 + echo "$rtime" >"$info_dir/oldtime"
42 + exit 0
43 +else
44 + # Current commit is considered "bad/new"
45 + echo "$rtime" >"$info_dir/newtime"
46 + exit 1
47 +fi