From 201628f87fbdecc81126399cf111f57ea20fa321 Mon Sep 17 00:00:00 2001
From: Thomas Haller <thaller@redhat.com>
Date: Tue, 19 Mar 2024 08:58:01 +0100
Subject: [PATCH] gobject/performance: improve "performance-run.sh" script

- fix and improve usage output for "performance-run.sh" script.

- add a sleep after compilation. It seems to me, that the first run
  usually performs better, which might be because the temperature of the
  CPU raises and the CPU gets throttled. Unclear whether that is really
  the case, but add a sleep so that all runs start under similar
  conditions where the CPU was idle for a moment.
---
 gobject/tests/performance/performance-run.sh | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/gobject/tests/performance/performance-run.sh b/gobject/tests/performance/performance-run.sh
index 3bc64a9fd..341149b41 100755
--- a/gobject/tests/performance/performance-run.sh
+++ b/gobject/tests/performance/performance-run.sh
@@ -11,11 +11,14 @@
 #
 # 1) configure the build. For example run
 #     $ git clean -fdx
-#     $ meson build -Dprefix=/tmp/glib/ -Db_lto=true --buildtype release -Ddebug=true
+#     $ meson build -Dprefix=/tmp/glib/ -Db_lto=true --buildtype release -Ddebug=false
 #    Beware, that running the script will check out other commits,
 #    build the tree and run `ninja install`. Don't have important
 #    work there.
 #
+#    Consider setting `echo performance | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor`
+#    and check `watch cat /sys/devices/system/cpu/cpu[0-9]*/cpufreq/scaling_cur_freq`.
+#
 # 2) run the script. Set $COMMITS to the list of commit sha's to test.
 #    Environment variables:
 #      COMMITS: list of git references to test.
@@ -33,23 +36,23 @@
 #
 #    # once:
 #    git clean -fdx
-#    meson build -Dprefix=/tmp/glib/ -Db_lto=true --buildtype release -Ddebug=true
+#    meson build -Dprefix=/tmp/glib/ -Db_lto=true --buildtype release -Ddebug=false
 #
 #    # test:
 #    COMMIT_END=my-test-branch
 #    COMMIT_START="$(git merge-base origin/main "$COMMIT_END")"
-#    PERF="" PATCH="" COMMITS=" $COMMIT_START $COMMIT_END " /tmp/performance-run.sh -s 5
-#    PERF="" PATCH="" COMMITS=" $COMMIT_START $( git log --reverse --pretty=%H "$COMMIT_START..$COMMIT_END" ) " /tmp/performance-run.sh -s 5
+#    PERF="" PATCH="" COMMITS=" $COMMIT_START $COMMIT_END " /tmp/performance-run.sh -q -s 5
+#    PERF="" PATCH="" COMMITS=" $COMMIT_START $( git log --reverse --pretty=%H "$COMMIT_START..$COMMIT_END" ) " /tmp/performance-run.sh -q -s 5
 #
-#    GLIB_PERFORMANCE_FACTOR=17.06 PERF='perf stat -r 3 -B' PATCH="" COMMITS=" $COMMIT_START $COMMIT_END " /tmp/performance-run.sh -s 1 property-get
+#    GLIB_PERFORMANCE_FACTOR=1 PERF='perf stat -r 3 -B' PATCH="" COMMITS=" $COMMIT_START $COMMIT_END " /tmp/performance-run.sh -q -s 1 property-get
 
 set -e
 
 usage() {
-    sed -n '4,/^$/ s/^#\( \(.*\)\|\)$/\2/p' "$0"
+    sed -n '/^# Run /,/^$/ s/^#\( \(.*\)\|\)$/\2/p' "$0"
 }
 
-if [ "$#" -eq 1 ] && [ "$1" == "-h" ] ; then
+if [[ "$#" -eq 1 && ( "$1" == "-h" || "$1" == "--help" ) ]]; then
     usage
     exit 0
 fi
@@ -92,7 +95,7 @@ Testing commits:
 
 $(_list_commits "    ")
 
-  \$ meson build -Dprefix=/tmp/glib/ -Db_lto=true --buildtype release -Ddebug=true
+  \$ meson build -Dprefix=/tmp/glib/ -Db_lto=true --buildtype release -Ddebug=false
   \$ PATCH=$(printf '%q' "$PATCH") \\
     PREPARE_CMD=$(printf '%q' "$PREPARE_CMD") \\
     PERF=$(printf '%q' "$PERF") \\
@@ -151,6 +154,7 @@ for idx in "${!COMMITS_V[@]}" ; do
     #     ./build/gobject/tests/performance/performance
     # ldd ./build/gobject/tests/performance/performance
 
+    sleep 2
     (
         if [ -z "$PERF" ] ; then
             TESTRUN="$I" TESTCOMMIT="$commit" ./build/gobject/tests/performance/performance "$@"