benchmark-chromium.sh

#!/usr/bin/env zsh
# Usage: benchmark-chromium.sh <path/to/chrome> <url> <run count> [path/to/results] [extra chrome arguments ...]
set -euo pipefail
script_dir=${0:a:h}
chromium=$1; shift
url=$1; shift
run_count=$1; shift
results=${1-$(mktemp -d)}
if [ $# -gt 0 ]; then
    shift
fi
browser_open_time=${SERVO_PERF_BROWSER_OPEN_TIME-10}

mkdir -p "$results"
if [ -e "$results/done" ]; then
    echo ">>> $results is done; skipping"
    exit
fi
rm -f "$results/*"

for i in {01..$run_count}; do
    echo ">>> $i"

    # Fresh --user-data-dir to avoid interfering with user’s default profile
    # and avoid disk caching. Disk caching helps control for network performance
    # but it may unfairly punish Servo.
    # <https://peter.sh/experiments/chromium-command-line-switches/#user-data-dir>
    # <https://peter.sh/experiments/chromium-command-line-switches/#no-first-run>
    profile=$(mktemp -d)
    "$chromium" \
        --user-data-dir="$profile" --no-first-run \
        --trace-startup --trace-startup-file="$results/chrome$i.pftrace" \
        --ignore-certificate-errors \
        "$@" \
        "$url" &
    pid=$!

    # Resize the visible Chromium window with our pid to the same size as default servoshell.
    # TODO: can we have both Servo and Chromium windows at the same size before loading a page?
    printf 'Resizing window'
    while ! xdotool search --sync --all --pid $pid --role browser windowsize 1024 740; do
        printf .
        sleep 1
    done
    echo

    sleep "$browser_open_time"
    # Close that window gracefully. Chromium does not write a trace file if sent a SIGTERM.
    printf 'Closing window'
    while kill -0 $pid 2> /dev/null; do
        # No --sync here, because the window may be gone by now.
        xdotool search --all --pid $pid --role browser windowquit || :
        printf .
        sleep 1
    done
    echo
    while ! rm -R "$profile"; do
        >&2 echo 'Failed to delete Chromium profile; will retry'
        sleep 1
    done
    echo
    echo
done

touch "$results/done"
echo "Results: $results"