tools/gc-nvp-trace-processor.py - fp2-dev/platform/external/v8 - Gitiles

 #!/usr/bin/env python
 #
 # Copyright 2010 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
 #       with the distribution.
 #     * Neither the name of Google Inc. nor the names of its
 #       contributors may be used to endorse or promote products derived
 #       from this software without specific prior written permission.
 #
 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #

 #
 # This is an utility for plotting charts based on GC traces produced by V8 when
 # run with flags --trace-gc --trace-gc-nvp. Relies on gnuplot for actual
 # plotting.
 #
 # Usage: gc-nvp-trace-processor.py <GC-trace-filename>
 #


 from __future__ import with_statement
 import sys, types, re, subprocess, math

 def flatten(l):
   flat = []
   for i in l: flat.extend(i)
   return flat

 def split_nvp(s):
   t = {}
   for (name, value) in re.findall(r"(\w+)=([-\w]+)", s):
     try:
       t[name] = int(value)
     except ValueError:
       t[name] = value

   return t

 def parse_gc_trace(input):
   trace = []
   with open(input) as f:
     for line in f:
       info = split_nvp(line)
       if info and 'pause' in info and info['pause'] > 0:
         info['i'] = len(trace)
         trace.append(info)
   return trace

 def extract_field_names(script):
   fields = { 'data': true, 'in': true }

   for m in re.finditer(r"$(\w+)", script):
     field_name = m.group(1)
     if field_name not in fields:
       fields[field] = field_count
       field_count = field_count + 1

   return fields

 def gnuplot(script):
   gnuplot = subprocess.Popen(["gnuplot"], stdin=subprocess.PIPE)
   gnuplot.stdin.write(script)
   gnuplot.stdin.close()
   gnuplot.wait()

 x1y1 = 'x1y1'
 x1y2 = 'x1y2'
 x2y1 = 'x2y1'
 x2y2 = 'x2y2'

 class Item(object):
   def __init__(self, title, field, axis = x1y1, **keywords):
     self.title = title
     self.axis = axis
     self.props = keywords
     if type(field) is types.ListType:
       self.field = field
     else:
       self.field = [field]

   def fieldrefs(self):
     return self.field

   def to_gnuplot(self, context):
     args = ['"%s"' % context.datafile,
             'using %s' % context.format_fieldref(self.field),
             'title "%s"' % self.title,
             'axis %s' % self.axis]
     if 'style' in self.props:
       args.append('with %s' % self.props['style'])
     if 'lc' in self.props:
       args.append('lc rgb "%s"' % self.props['lc'])
     if 'fs' in self.props:
       args.append('fs %s' % self.props['fs'])
     return ' '.join(args)

 class Plot(object):
   def __init__(self, *items):
     self.items = items

   def fieldrefs(self):
     return flatten([item.fieldrefs() for item in self.items])

   def to_gnuplot(self, ctx):
     return 'plot ' + ', '.join([item.to_gnuplot(ctx) for item in self.items])

 class Set(object):
   def __init__(self, value):
     self.value = value

   def to_gnuplot(self, ctx):
     return 'set ' + self.value

   def fieldrefs(self):
     return []

 class Context(object):
   def __init__(self, datafile, field_to_index):
     self.datafile = datafile
     self.field_to_index = field_to_index

   def format_fieldref(self, fieldref):
     return ':'.join([str(self.field_to_index[field]) for field in fieldref])

 def collect_fields(plot):
   field_to_index = {}
   fields = []

   def add_field(field):
     if field not in field_to_index:
       fields.append(field)
       field_to_index[field] = len(fields)

   for field in flatten([item.fieldrefs() for item in plot]):
     add_field(field)

   return (fields, field_to_index)

 def is_y2_used(plot):
   for subplot in plot:
     if isinstance(subplot, Plot):
       for item in subplot.items:
         if item.axis == x1y2 or item.axis == x2y2:
           return True
   return False

 def get_field(trace_line, field):
   t = type(field)
   if t is types.StringType:
     return trace_line[field]
   elif t is types.FunctionType:
     return field(trace_line)

 def generate_datafile(datafile_name, trace, fields):
   with open(datafile_name, 'w') as datafile:
     for line in trace:
       data_line = [str(get_field(line, field)) for field in fields]
       datafile.write('\t'.join(data_line))
       datafile.write('\n')

 def generate_script_and_datafile(plot, trace, datafile, output):
   (fields, field_to_index) = collect_fields(plot)
   generate_datafile(datafile, trace, fields)
   script = [
       'set terminal png',
       'set output "%s"' % output,
       'set autoscale',
       'set ytics nomirror',
       'set xtics nomirror',
       'set key below'
   ]

   if is_y2_used(plot):
     script.append('set autoscale y2')
     script.append('set y2tics')

   context = Context(datafile, field_to_index)

   for item in plot:
     script.append(item.to_gnuplot(context))

   return '\n'.join(script)

 def plot_all(plots, trace, prefix):
   charts = []

   for plot in plots:
     outfilename = "%s_%d.png" % (prefix, len(charts))
     charts.append(outfilename)
     script = generate_script_and_datafile(plot, trace, '~datafile', outfilename)
     print 'Plotting %s...' % outfilename
     gnuplot(script)

   return charts

 def reclaimed_bytes(row):
   return row['total_size_before'] - row['total_size_after']

 def other_scope(r):
   if r['gc'] == 's':
     # there is no 'other' scope for scavenging collections.
     return 0
   return r['pause'] - r['mark'] - r['sweep'] - r['external']

 def scavenge_scope(r):
   if r['gc'] == 's':
     return r['pause'] - r['external']
   return 0


 def real_mutator(r):
   return r['mutator'] - r['stepstook']

 plots = [
   [
     Set('style fill solid 0.5 noborder'),
     Set('style histogram rowstacked'),
     Set('style data histograms'),
     Plot(Item('Scavenge', scavenge_scope, lc = 'green'),
          Item('Marking', 'mark', lc = 'purple'),
          Item('Sweep', 'sweep', lc = 'blue'),
          Item('External', 'external', lc = '#489D43'),
          Item('Other', other_scope, lc = 'grey'),
          Item('IGC Steps', 'stepstook', lc = '#FF6347'))
   ],
   [
     Set('style fill solid 0.5 noborder'),
     Set('style histogram rowstacked'),
     Set('style data histograms'),
     Plot(Item('Scavenge', scavenge_scope, lc = 'green'),
          Item('Marking', 'mark', lc = 'purple'),
          Item('Sweep', 'sweep', lc = 'blue'),
          Item('External', 'external', lc = '#489D43'),
          Item('Other', other_scope, lc = '#ADD8E6'),
          Item('External', 'external', lc = '#D3D3D3'))
   ],

   [
     Plot(Item('Mutator', real_mutator, lc = 'black', style = 'lines'))
   ],
   [
     Set('style histogram rowstacked'),
     Set('style data histograms'),
     Plot(Item('Heap Size (before GC)', 'total_size_before', x1y2,
               fs = 'solid 0.4 noborder',
               lc = 'green'),
          Item('Total holes (after GC)', 'holes_size_before', x1y2,
               fs = 'solid 0.4 noborder',
               lc = 'red'),
          Item('GC Time', ['i', 'pause'], style = 'lines', lc = 'red'))
   ],
   [
     Set('style histogram rowstacked'),
     Set('style data histograms'),
     Plot(Item('Heap Size (after GC)', 'total_size_after', x1y2,
               fs = 'solid 0.4 noborder',
               lc = 'green'),
          Item('Total holes (after GC)', 'holes_size_after', x1y2,
               fs = 'solid 0.4 noborder',
               lc = 'red'),
          Item('GC Time', ['i', 'pause'],
               style = 'lines',
               lc = 'red'))
   ],
   [
     Set('style fill solid 0.5 noborder'),
     Set('style data histograms'),
     Plot(Item('Allocated', 'allocated'),
          Item('Reclaimed', reclaimed_bytes),
          Item('Promoted', 'promoted', style = 'lines', lc = 'black'))
   ],
 ]

 def freduce(f, field, trace, init):
   return reduce(lambda t,r: f(t, r[field]), trace, init)

 def calc_total(trace, field):
   return freduce(lambda t,v: t + long(v), field, trace, long(0))

 def calc_max(trace, field):
   return freduce(lambda t,r: max(t, r), field, trace, 0)

 def count_nonzero(trace, field):
   return freduce(lambda t,r: t if r == 0 else t + 1, field, trace, 0)


 def process_trace(filename):
   trace = parse_gc_trace(filename)

   marksweeps = filter(lambda r: r['gc'] == 'ms', trace)
   scavenges = filter(lambda r: r['gc'] == 's', trace)
   globalgcs = filter(lambda r: r['gc'] != 's', trace)


   charts = plot_all(plots, trace, filename)

   def stats(out, prefix, trace, field):
     n = len(trace)
     total = calc_total(trace, field)
     max = calc_max(trace, field)
     if n > 0:
       avg = total / n
     else:
       avg = 0
     if n > 1:
       dev = math.sqrt(freduce(lambda t,r: t + (r - avg) ** 2, field, trace, 0) /
                       (n - 1))
     else:
       dev = 0

     out.write('<tr><td>%s</td><td>%d</td><td>%d</td>'
               '<td>%d</td><td>%d [dev %f]</td></tr>' %
               (prefix, n, total, max, avg, dev))

   def HumanReadable(size):
     suffixes = ['bytes', 'kB', 'MB', 'GB']
     power = 1
     for i in range(len(suffixes)):
       if size < power*1024:
         return "%.1f" % (float(size) / power) + " " + suffixes[i]
       power *= 1024

   def throughput(name, trace):
     total_live_after = calc_total(trace, 'total_size_after')
     total_live_before = calc_total(trace, 'total_size_before')
     total_gc = calc_total(trace, 'pause')
     if total_gc == 0:
       return
     out.write('GC %s Throughput (after): %s / %s ms = %s/ms<br/>' %
               (name,
                HumanReadable(total_live_after),
                total_gc,
                HumanReadable(total_live_after / total_gc)))
     out.write('GC %s Throughput (before): %s / %s ms = %s/ms<br/>' %
               (name,
                HumanReadable(total_live_before),
                total_gc,
                HumanReadable(total_live_before / total_gc)))


   with open(filename + '.html', 'w') as out:
     out.write('<html><body>')
     out.write('<table>')
     out.write('<tr><td>Phase</td><td>Count</td><td>Time (ms)</td>')
     out.write('<td>Max</td><td>Avg</td></tr>')
     stats(out, 'Total in GC', trace, 'pause')
     stats(out, 'Scavenge', scavenges, 'pause')
     stats(out, 'MarkSweep', marksweeps, 'pause')
     stats(out, 'Mark', filter(lambda r: r['mark'] != 0, trace), 'mark')
     stats(out, 'Sweep', filter(lambda r: r['sweep'] != 0, trace), 'sweep')
     stats(out,
           'External',
           filter(lambda r: r['external'] != 0, trace),
           'external')
     out.write('</table>')
     throughput('TOTAL', trace)
     throughput('MS', marksweeps)
     throughput('OLDSPACE', globalgcs)
     out.write('<br/>')
     for chart in charts:
       out.write('<img src="%s">' % chart)
       out.write('</body></html>')

   print "%s generated." % (filename + '.html')

 if len(sys.argv) != 2:
   print "Usage: %s <GC-trace-filename>" % sys.argv[0]
   sys.exit(1)

 process_trace(sys.argv[1])
	#!/usr/bin/env python
	#
	# Copyright 2010 the V8 project authors. All rights reserved.
	# Redistribution and use in source and binary forms, with or without
	# modification, are permitted provided that the following conditions are
	# met:
	#
	# * Redistributions of source code must retain the above copyright
	# notice, this list of conditions and the following disclaimer.
	# * Redistributions in binary form must reproduce the above
	# copyright notice, this list of conditions and the following
	# disclaimer in the documentation and/or other materials provided
	# with the distribution.
	# * Neither the name of Google Inc. nor the names of its
	# contributors may be used to endorse or promote products derived
	# from this software without specific prior written permission.
	#
	# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	#

	#
	# This is an utility for plotting charts based on GC traces produced by V8 when
	# run with flags --trace-gc --trace-gc-nvp. Relies on gnuplot for actual
	# plotting.
	#
	# Usage: gc-nvp-trace-processor.py <GC-trace-filename>
	#


	from __future__ import with_statement
	import sys, types, re, subprocess, math

	def flatten(l):
	flat = []
	for i in l: flat.extend(i)
	return flat

	def split_nvp(s):
	t = {}
	for (name, value) in re.findall(r"(\w+)=([-\w]+)", s):
	try:
	t[name] = int(value)
	except ValueError:
	t[name] = value

	return t

	def parse_gc_trace(input):
	trace = []
	with open(input) as f:
	for line in f:
	info = split_nvp(line)
	if info and 'pause' in info and info['pause'] > 0:
	info['i'] = len(trace)
	trace.append(info)
	return trace

	def extract_field_names(script):
	fields = { 'data': true, 'in': true }

	for m in re.finditer(r"$(\w+)", script):
	field_name = m.group(1)
	if field_name not in fields:
	fields[field] = field_count
	field_count = field_count + 1

	return fields

	def gnuplot(script):
	gnuplot = subprocess.Popen(["gnuplot"], stdin=subprocess.PIPE)
	gnuplot.stdin.write(script)
	gnuplot.stdin.close()
	gnuplot.wait()

	x1y1 = 'x1y1'
	x1y2 = 'x1y2'
	x2y1 = 'x2y1'
	x2y2 = 'x2y2'

	class Item(object):
	def __init__(self, title, field, axis = x1y1, **keywords):
	self.title = title
	self.axis = axis
	self.props = keywords
	if type(field) is types.ListType:
	self.field = field
	else:
	self.field = [field]

	def fieldrefs(self):
	return self.field

	def to_gnuplot(self, context):
	args = ['"%s"' % context.datafile,
	'using %s' % context.format_fieldref(self.field),
	'title "%s"' % self.title,
	'axis %s' % self.axis]
	if 'style' in self.props:
	args.append('with %s' % self.props['style'])
	if 'lc' in self.props:
	args.append('lc rgb "%s"' % self.props['lc'])
	if 'fs' in self.props:
	args.append('fs %s' % self.props['fs'])
	return ' '.join(args)

	class Plot(object):
	def __init__(self, *items):
	self.items = items

	def fieldrefs(self):
	return flatten([item.fieldrefs() for item in self.items])

	def to_gnuplot(self, ctx):
	return 'plot ' + ', '.join([item.to_gnuplot(ctx) for item in self.items])

	class Set(object):
	def __init__(self, value):
	self.value = value

	def to_gnuplot(self, ctx):
	return 'set ' + self.value

	def fieldrefs(self):
	return []

	class Context(object):
	def __init__(self, datafile, field_to_index):
	self.datafile = datafile
	self.field_to_index = field_to_index

	def format_fieldref(self, fieldref):
	return ':'.join([str(self.field_to_index[field]) for field in fieldref])

	def collect_fields(plot):
	field_to_index = {}
	fields = []

	def add_field(field):
	if field not in field_to_index:
	fields.append(field)
	field_to_index[field] = len(fields)

	for field in flatten([item.fieldrefs() for item in plot]):
	add_field(field)

	return (fields, field_to_index)

	def is_y2_used(plot):
	for subplot in plot:
	if isinstance(subplot, Plot):
	for item in subplot.items:
	if item.axis == x1y2 or item.axis == x2y2:
	return True
	return False

	def get_field(trace_line, field):
	t = type(field)
	if t is types.StringType:
	return trace_line[field]
	elif t is types.FunctionType:
	return field(trace_line)

	def generate_datafile(datafile_name, trace, fields):
	with open(datafile_name, 'w') as datafile:
	for line in trace:
	data_line = [str(get_field(line, field)) for field in fields]
	datafile.write('\t'.join(data_line))
	datafile.write('\n')

	def generate_script_and_datafile(plot, trace, datafile, output):
	(fields, field_to_index) = collect_fields(plot)
	generate_datafile(datafile, trace, fields)
	script = [
	'set terminal png',
	'set output "%s"' % output,
	'set autoscale',
	'set ytics nomirror',
	'set xtics nomirror',
	'set key below'
	]

	if is_y2_used(plot):
	script.append('set autoscale y2')
	script.append('set y2tics')

	context = Context(datafile, field_to_index)

	for item in plot:
	script.append(item.to_gnuplot(context))

	return '\n'.join(script)

	def plot_all(plots, trace, prefix):
	charts = []

	for plot in plots:
	outfilename = "%s_%d.png" % (prefix, len(charts))
	charts.append(outfilename)
	script = generate_script_and_datafile(plot, trace, '~datafile', outfilename)
	print 'Plotting %s...' % outfilename
	gnuplot(script)

	return charts

	def reclaimed_bytes(row):
	return row['total_size_before'] - row['total_size_after']

	def other_scope(r):
	if r['gc'] == 's':
	# there is no 'other' scope for scavenging collections.
	return 0
	return r['pause'] - r['mark'] - r['sweep'] - r['external']

	def scavenge_scope(r):
	if r['gc'] == 's':
	return r['pause'] - r['external']
	return 0


	def real_mutator(r):
	return r['mutator'] - r['stepstook']

	plots = [
	[
	Set('style fill solid 0.5 noborder'),
	Set('style histogram rowstacked'),
	Set('style data histograms'),
	Plot(Item('Scavenge', scavenge_scope, lc = 'green'),
	Item('Marking', 'mark', lc = 'purple'),
	Item('Sweep', 'sweep', lc = 'blue'),
	Item('External', 'external', lc = '#489D43'),
	Item('Other', other_scope, lc = 'grey'),
	Item('IGC Steps', 'stepstook', lc = '#FF6347'))
	],
	[
	Set('style fill solid 0.5 noborder'),
	Set('style histogram rowstacked'),
	Set('style data histograms'),
	Plot(Item('Scavenge', scavenge_scope, lc = 'green'),
	Item('Marking', 'mark', lc = 'purple'),
	Item('Sweep', 'sweep', lc = 'blue'),
	Item('External', 'external', lc = '#489D43'),
	Item('Other', other_scope, lc = '#ADD8E6'),
	Item('External', 'external', lc = '#D3D3D3'))
	],

	[
	Plot(Item('Mutator', real_mutator, lc = 'black', style = 'lines'))
	],
	[
	Set('style histogram rowstacked'),
	Set('style data histograms'),
	Plot(Item('Heap Size (before GC)', 'total_size_before', x1y2,
	fs = 'solid 0.4 noborder',
	lc = 'green'),
	Item('Total holes (after GC)', 'holes_size_before', x1y2,
	fs = 'solid 0.4 noborder',
	lc = 'red'),
	Item('GC Time', ['i', 'pause'], style = 'lines', lc = 'red'))
	],
	[
	Set('style histogram rowstacked'),
	Set('style data histograms'),
	Plot(Item('Heap Size (after GC)', 'total_size_after', x1y2,
	fs = 'solid 0.4 noborder',
	lc = 'green'),
	Item('Total holes (after GC)', 'holes_size_after', x1y2,
	fs = 'solid 0.4 noborder',
	lc = 'red'),
	Item('GC Time', ['i', 'pause'],
	style = 'lines',
	lc = 'red'))
	],
	[
	Set('style fill solid 0.5 noborder'),
	Set('style data histograms'),
	Plot(Item('Allocated', 'allocated'),
	Item('Reclaimed', reclaimed_bytes),
	Item('Promoted', 'promoted', style = 'lines', lc = 'black'))
	],
	]

	def freduce(f, field, trace, init):
	return reduce(lambda t,r: f(t, r[field]), trace, init)

	def calc_total(trace, field):
	return freduce(lambda t,v: t + long(v), field, trace, long(0))

	def calc_max(trace, field):
	return freduce(lambda t,r: max(t, r), field, trace, 0)

	def count_nonzero(trace, field):
	return freduce(lambda t,r: t if r == 0 else t + 1, field, trace, 0)


	def process_trace(filename):
	trace = parse_gc_trace(filename)

	marksweeps = filter(lambda r: r['gc'] == 'ms', trace)
	scavenges = filter(lambda r: r['gc'] == 's', trace)
	globalgcs = filter(lambda r: r['gc'] != 's', trace)


	charts = plot_all(plots, trace, filename)

	def stats(out, prefix, trace, field):
	n = len(trace)
	total = calc_total(trace, field)
	max = calc_max(trace, field)
	if n > 0:
	avg = total / n
	else:
	avg = 0
	if n > 1:
	dev = math.sqrt(freduce(lambda t,r: t + (r - avg) ** 2, field, trace, 0) /
	(n - 1))
	else:
	dev = 0

	out.write('<tr><td>%s</td><td>%d</td><td>%d</td>'
	'<td>%d</td><td>%d [dev %f]</td></tr>' %
	(prefix, n, total, max, avg, dev))

	def HumanReadable(size):
	suffixes = ['bytes', 'kB', 'MB', 'GB']
	power = 1
	for i in range(len(suffixes)):
	if size < power*1024:
	return "%.1f" % (float(size) / power) + " " + suffixes[i]
	power *= 1024

	def throughput(name, trace):
	total_live_after = calc_total(trace, 'total_size_after')
	total_live_before = calc_total(trace, 'total_size_before')
	total_gc = calc_total(trace, 'pause')
	if total_gc == 0:
	return
	out.write('GC %s Throughput (after): %s / %s ms = %s/ms<br/>' %
	(name,
	HumanReadable(total_live_after),
	total_gc,
	HumanReadable(total_live_after / total_gc)))
	out.write('GC %s Throughput (before): %s / %s ms = %s/ms<br/>' %
	(name,
	HumanReadable(total_live_before),
	total_gc,
	HumanReadable(total_live_before / total_gc)))


	with open(filename + '.html', 'w') as out:
	out.write('<html><body>')
	out.write('<table>')
	out.write('<tr><td>Phase</td><td>Count</td><td>Time (ms)</td>')
	out.write('<td>Max</td><td>Avg</td></tr>')
	stats(out, 'Total in GC', trace, 'pause')
	stats(out, 'Scavenge', scavenges, 'pause')
	stats(out, 'MarkSweep', marksweeps, 'pause')
	stats(out, 'Mark', filter(lambda r: r['mark'] != 0, trace), 'mark')
	stats(out, 'Sweep', filter(lambda r: r['sweep'] != 0, trace), 'sweep')
	stats(out,
	'External',
	filter(lambda r: r['external'] != 0, trace),
	'external')
	out.write('</table>')
	throughput('TOTAL', trace)
	throughput('MS', marksweeps)
	throughput('OLDSPACE', globalgcs)
	out.write('<br/>')
	for chart in charts:
	out.write('<img src="%s">' % chart)
	out.write('</body></html>')

	print "%s generated." % (filename + '.html')

	if len(sys.argv) != 2:
	print "Usage: %s <GC-trace-filename>" % sys.argv[0]
	sys.exit(1)

	process_trace(sys.argv[1])