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Tip revision: 8e2202c1ff770f6708cee75c0ff0f9fc4ce2af97 authored by ffxbld on 25 April 2012, 19:30:17 UTC
Added FENNEC_13_0b1_RELEASE FENNEC_13_0b1_BUILD1 tag(s) for changeset e8c31168413b. DONTBUILD CLOSED TREE a=release
Added FENNEC_13_0b1_RELEASE FENNEC_13_0b1_BUILD1 tag(s) for changeset e8c31168413b. DONTBUILD CLOSED TREE a=release
Tip revision: 8e2202c
Statistics.cpp
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sw=4 et tw=78:
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is SpiderMonkey JavaScript engine.
*
* The Initial Developer of the Original Code is
* the Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2011
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include <stdio.h>
#include <stdarg.h>
#include "jscntxt.h"
#include "jscompartment.h"
#include "jscrashformat.h"
#include "jscrashreport.h"
#include "jsprf.h"
#include "jsprobes.h"
#include "jsutil.h"
#include "prmjtime.h"
#include "gc/Statistics.h"
namespace js {
namespace gcstats {
static const char *
ExplainReason(gcreason::Reason reason)
{
switch (reason) {
#define SWITCH_REASON(name) \
case gcreason::name: \
return #name;
GCREASONS(SWITCH_REASON)
default:
JS_NOT_REACHED("bad GC reason");
return "?";
#undef SWITCH_REASON
}
}
void
Statistics::fmt(const char *f, ...)
{
va_list va;
size_t off = strlen(buffer);
va_start(va, f);
JS_vsnprintf(buffer + off, BUFFER_SIZE - off, f, va);
va_end(va);
}
void
Statistics::fmtIfNonzero(const char *name, double t)
{
if (t) {
if (needComma)
fmt(", ");
fmt("%s: %.1f", name, t);
needComma = true;
}
}
void
Statistics::formatPhases(int64_t *times)
{
needComma = false;
fmtIfNonzero("mark", t(times[PHASE_MARK]));
fmtIfNonzero("mark-roots", t(times[PHASE_MARK_ROOTS]));
fmtIfNonzero("mark-delayed", t(times[PHASE_MARK_DELAYED]));
fmtIfNonzero("mark-other", t(times[PHASE_MARK_OTHER]));
fmtIfNonzero("sweep", t(times[PHASE_SWEEP]));
fmtIfNonzero("sweep-obj", t(times[PHASE_SWEEP_OBJECT]));
fmtIfNonzero("sweep-string", t(times[PHASE_SWEEP_STRING]));
fmtIfNonzero("sweep-script", t(times[PHASE_SWEEP_SCRIPT]));
fmtIfNonzero("sweep-shape", t(times[PHASE_SWEEP_SHAPE]));
fmtIfNonzero("discard-code", t(times[PHASE_DISCARD_CODE]));
fmtIfNonzero("discard-analysis", t(times[PHASE_DISCARD_ANALYSIS]));
fmtIfNonzero("xpconnect", t(times[PHASE_XPCONNECT]));
fmtIfNonzero("deallocate", t(times[PHASE_DESTROY]));
}
/* Except for the first and last, slices of less than 12ms are not reported. */
static const int64_t SLICE_MIN_REPORT_TIME = 12 * PRMJ_USEC_PER_MSEC;
const char *
Statistics::formatData()
{
buffer[0] = 0x00;
int64_t total = 0, longest = 0;
for (SliceData *slice = slices.begin(); slice != slices.end(); slice++) {
total += slice->duration();
if (slice->duration() > longest)
longest = slice->duration();
}
double mmu20 = computeMMU(20 * PRMJ_USEC_PER_MSEC);
double mmu50 = computeMMU(50 * PRMJ_USEC_PER_MSEC);
fmt("TotalTime: %.1fms, Type: %s", t(total), compartment ? "compartment" : "global");
fmt(", MMU(20ms): %d%%, MMU(50ms): %d%%", int(mmu20 * 100), int(mmu50 * 100));
if (slices.length() > 1)
fmt(", MaxPause: %.1f", t(longest));
else
fmt(", Reason: %s", ExplainReason(slices[0].reason));
if (nonincrementalReason)
fmt(", NonIncrementalReason: %s", nonincrementalReason);
fmt(", +chunks: %d, -chunks: %d\n", counts[STAT_NEW_CHUNK], counts[STAT_DESTROY_CHUNK]);
if (slices.length() > 1) {
for (size_t i = 0; i < slices.length(); i++) {
int64_t width = slices[i].duration();
if (i != 0 && i != slices.length() - 1 && width < SLICE_MIN_REPORT_TIME &&
!slices[i].resetReason)
{
continue;
}
fmt(" Slice %d @ %.1fms (Pause: %.1f, Reason: %s",
i,
t(slices[i].end - slices[0].start),
t(width),
ExplainReason(slices[i].reason));
if (slices[i].resetReason)
fmt(", Reset: %s", slices[i].resetReason);
fmt("): ");
formatPhases(slices[i].phaseTimes);
fmt("\n");
}
fmt(" Totals: ");
}
formatPhases(phaseTimes);
fmt("\n");
return buffer;
}
Statistics::Statistics(JSRuntime *rt)
: runtime(rt),
startupTime(PRMJ_Now()),
fp(NULL),
fullFormat(false),
compartment(NULL),
nonincrementalReason(NULL),
needComma(false)
{
PodArrayZero(phaseTotals);
PodArrayZero(counts);
char *env = getenv("MOZ_GCTIMER");
if (!env || strcmp(env, "none") == 0) {
fp = NULL;
return;
}
if (strcmp(env, "stdout") == 0) {
fullFormat = false;
fp = stdout;
} else if (strcmp(env, "stderr") == 0) {
fullFormat = false;
fp = stderr;
} else {
fullFormat = true;
fp = fopen(env, "a");
JS_ASSERT(fp);
}
}
Statistics::~Statistics()
{
if (fp) {
if (fullFormat) {
buffer[0] = 0x00;
formatPhases(phaseTotals);
fprintf(fp, "TOTALS\n%s\n\n-------\n", buffer);
}
if (fp != stdout && fp != stderr)
fclose(fp);
}
}
double
Statistics::t(int64_t t)
{
return double(t) / PRMJ_USEC_PER_MSEC;
}
int64_t
Statistics::gcDuration()
{
return slices.back().end - slices[0].start;
}
void
Statistics::printStats()
{
if (fullFormat) {
fprintf(fp, "GC(T+%.3fs) %s\n",
t(slices[0].start - startupTime) / 1000.0,
formatData());
} else {
fprintf(fp, "%f %f %f\n",
t(gcDuration()),
t(phaseTimes[PHASE_MARK]),
t(phaseTimes[PHASE_SWEEP]));
}
fflush(fp);
}
void
Statistics::beginGC()
{
PodArrayZero(phaseStarts);
PodArrayZero(phaseTimes);
slices.clearAndFree();
nonincrementalReason = NULL;
Probes::GCStart();
}
void
Statistics::endGC()
{
Probes::GCEnd();
crash::SnapshotGCStack();
for (int i = 0; i < PHASE_LIMIT; i++)
phaseTotals[i] += phaseTimes[i];
if (JSAccumulateTelemetryDataCallback cb = runtime->telemetryCallback) {
(*cb)(JS_TELEMETRY_GC_IS_COMPARTMENTAL, compartment ? 1 : 0);
(*cb)(JS_TELEMETRY_GC_MS, t(gcDuration()));
(*cb)(JS_TELEMETRY_GC_MARK_MS, t(phaseTimes[PHASE_MARK]));
(*cb)(JS_TELEMETRY_GC_SWEEP_MS, t(phaseTimes[PHASE_SWEEP]));
(*cb)(JS_TELEMETRY_GC_NON_INCREMENTAL, !!nonincrementalReason);
(*cb)(JS_TELEMETRY_GC_INCREMENTAL_DISABLED, !runtime->gcIncrementalEnabled);
double mmu50 = computeMMU(50 * PRMJ_USEC_PER_MSEC);
(*cb)(JS_TELEMETRY_GC_MMU_50, mmu50 * 100);
}
if (fp)
printStats();
PodArrayZero(counts);
}
void
Statistics::beginSlice(JSCompartment *comp, gcreason::Reason reason)
{
compartment = comp;
bool first = runtime->gcIncrementalState == gc::NO_INCREMENTAL;
if (first)
beginGC();
SliceData data(reason, PRMJ_Now());
(void) slices.append(data); /* Ignore any OOMs here. */
if (JSAccumulateTelemetryDataCallback cb = runtime->telemetryCallback)
(*cb)(JS_TELEMETRY_GC_REASON, reason);
if (GCSliceCallback cb = runtime->gcSliceCallback) {
GCDescription desc(NULL, !!compartment);
(*cb)(runtime, first ? GC_CYCLE_BEGIN : GC_SLICE_BEGIN, desc);
}
}
void
Statistics::endSlice()
{
slices.back().end = PRMJ_Now();
if (JSAccumulateTelemetryDataCallback cb = runtime->telemetryCallback) {
(*cb)(JS_TELEMETRY_GC_SLICE_MS, t(slices.back().end - slices.back().start));
(*cb)(JS_TELEMETRY_GC_RESET, !!slices.back().resetReason);
}
bool last = runtime->gcIncrementalState == gc::NO_INCREMENTAL;
if (last)
endGC();
if (GCSliceCallback cb = runtime->gcSliceCallback) {
if (last)
(*cb)(runtime, GC_CYCLE_END, GCDescription(formatData(), !!compartment));
else
(*cb)(runtime, GC_SLICE_END, GCDescription(NULL, !!compartment));
}
}
void
Statistics::beginPhase(Phase phase)
{
phaseStarts[phase] = PRMJ_Now();
if (phase == gcstats::PHASE_MARK)
Probes::GCStartMarkPhase();
else if (phase == gcstats::PHASE_SWEEP)
Probes::GCStartSweepPhase();
}
void
Statistics::endPhase(Phase phase)
{
int64_t now = PRMJ_Now();
int64_t t = now - phaseStarts[phase];
slices.back().phaseTimes[phase] += t;
phaseTimes[phase] += t;
if (phase == gcstats::PHASE_MARK)
Probes::GCEndMarkPhase();
else if (phase == gcstats::PHASE_SWEEP)
Probes::GCEndSweepPhase();
}
/*
* MMU (minimum mutator utilization) is a measure of how much garbage collection
* is affecting the responsiveness of the system. MMU measurements are given
* with respect to a certain window size. If we report MMU(50ms) = 80%, then
* that means that, for any 50ms window of time, at least 80% of the window is
* devoted to the mutator. In other words, the GC is running for at most 20% of
* the window, or 10ms. The GC can run multiple slices during the 50ms window
* as long as the total time it spends is at most 10ms.
*/
double
Statistics::computeMMU(int64_t window)
{
JS_ASSERT(!slices.empty());
int64_t gc = slices[0].end - slices[0].start;
int64_t gcMax = gc;
if (gc >= window)
return 0.0;
int startIndex = 0;
for (size_t endIndex = 1; endIndex < slices.length(); endIndex++) {
gc += slices[endIndex].end - slices[endIndex].start;
while (slices[endIndex].end - slices[startIndex].end >= window) {
gc -= slices[startIndex].end - slices[startIndex].start;
startIndex++;
}
int64_t cur = gc;
if (slices[endIndex].end - slices[startIndex].start > window)
cur -= (slices[endIndex].end - slices[startIndex].start - window);
if (cur > gcMax)
gcMax = cur;
}
return double(window - gcMax) / window;
}
} /* namespace gcstats */
} /* namespace js */