blob: 68689265b4c075a40278de2958a1001bb8ce5e0f [file] [log] [blame]
// Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
//
// NOTE: See also wrapper script sdk/runtime/tools/bmu_benchmark_gallery.sh
//
// Tool to compute bounded mutator utilization (BMU) from a --verbose_gc log.
// Outputs CSV suitable for, e.g., gnuplot:
//
// dart --verbose_gc foo.dart 2> foo.gclog
// dart verbose_gc_to_bmu.dart < foo.gclog > foo.bmu
// gnuplot -p -e "set yr [0:1]; set logscale x; plot 'foo.bmu' with linespoints"
// @dart=2.9
import 'dart:io';
import 'dart:math';
const WINDOW_STEP_FACTOR = 0.9;
const MINIMUM_WINDOW_SIZE_MS = 1;
class Interval<T extends int> {
T begin;
T end;
Interval(this.begin, this.end);
T get length => max(0, end - begin);
Interval<T> overlap(Interval<T> other) =>
new Interval(max(this.begin, other.begin), min(this.end, other.end));
}
class Timeline {
// Pauses must be added in non-decreasing order of 'begin'.
void addPause(Interval<int> pause) {
var last = _pauses.isEmpty ? new Interval<int>(0, 0) : _pauses.last;
assert(last.begin <= pause.begin);
// Trim any initial overlap.
_pauses.add(new Interval(max(pause.begin, last.end), pause.end));
// TODO(koda): Make VM log actual end time, rather than just last GC end.
_run.end = max(_run.end, pause.end);
}
int get maxWindowSize => _run.length;
// The windowSize must be no larger than the entire run.
double minUtilization(int windowSize) {
assert(windowSize <= _run.length);
// The minimum utilization can always be found in a window that has one of
// its endpoints at the beginning or end of a pause or the entire timeline.
List<int> interesting = [_run.begin, _run.end];
for (Interval p in _pauses) {
interesting.add(p.begin);
interesting.add(p.end);
}
double result = 1.0;
for (int i in interesting) {
result = min(result, _utilization(new Interval(i, i + windowSize)));
result = min(result, _utilization(new Interval(i - windowSize, i)));
}
return result;
}
// Returns the fraction of non-pause time, or 1.0 for an invalid interval.
double _utilization(Interval<int> iv) {
if (_run.begin > iv.begin || iv.end > _run.end || iv.length == 0) {
return 1.0;
}
int paused = 0;
for (Interval<int> p in _pauses) {
paused += p.overlap(iv).length;
}
return 1.0 - (paused / iv.length);
}
final Interval<int> _run = new Interval<int>(0, 0);
final List<Interval<int>> _pauses = [];
}
// Returns a GC pause as an interval in microseconds since program start, or
// the interval [0, 0) on parse error.
Interval<int> parseVerboseGCLine(String line) {
var fields = line.split(',');
// Update this (and indices below, if needed) when logging format changes.
if (fields.length < 10) {
// Ignore the lines that just specify column names, separated by '|'.
// We assume these have very few commas in them, so that fields.length
// is < 10.
assert(line.contains("|"));
return new Interval<int>(0, 0);
}
var begin = (1e6 * double.parse(fields[2])).floor();
var duration = (1000 * double.parse(fields[3])).floor();
var end = begin + duration;
return new Interval<int>(begin, end);
}
void main() {
Timeline t = new Timeline();
for (String line = stdin.readLineSync();
line != null;
line = stdin.readLineSync()) {
t.addPause(parseVerboseGCLine(line));
}
print('# window_size_ms, bounded_mutator_utilization');
var minimumSeen = 1.0;
for (int w = t._run.length;
w > 1000 * MINIMUM_WINDOW_SIZE_MS;
w = (w * WINDOW_STEP_FACTOR).floor()) {
minimumSeen = min(minimumSeen, t.minUtilization(w));
print('${w / 1000}, $minimumSeen');
}
}