#!/usr/bin/env python

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# or more contributor license agreements.  See the NOTICE file
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# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
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#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.

"""Usage: benchmark.py run|list|compare|show|chart <selection> ...

SELECTING TIMINGS -- B@R,LxS

In the subcommands below, a timings selection consists of a string with up to
four elements:
  <branch>@<revision>,<levels>x<spread>
abbreviated as:
  B@R,LxS

<branch> is a label of an svn branch, e.g. "1.7.x".
<revision> is the last-changed-revision of above branch.
<levels> is the number of directory levels created in the benchmark.
<spread> is the number of child trees spreading off each dir level.

<branch_name> and <revision> are simply used for labeling. Upon the actual
test runs, you should enter labels matching the selected --svn-bin-dir.
Later, you can select runs individually by using these labels.

For <revision>, you can provide special keywords:
- 'each' has the same effect as entering each available revision number that
  is on record in the db in a separate timings selection.
- 'last' is the same as 'each', but shows only the last 10 revisions. 'last'
  can be combined with a number, e.g. 'last12'.

For all subcommands except 'run', you can omit some or all of the elements of
a timings selection to combine all available timings sets. Try that out with
the 'list' subcommand.

Examples:
  benchmark.py run 1.7.x@12345,5x5
  benchmark.py show trunk@12345
  benchmark.py compare 1.7.0,1x100 trunk@each,1x100
  benchmark.py chart compare 1.7.0,5x5 trunk@last12,5x5


RUN BENCHMARKS

  benchmark.py run B@R,LxS [N] [options]

Test data is added to an sqlite database created automatically, by default
'benchmark.db' in the current working directory. To specify a different path,
use option -f <path_to_db>.

If <N> is provided, the run is repeated N times.

<levels> and <spread> control the way the tested working copy is structured:
  <levels>: number of directory levels to create.
  <spread>: number of files and subdirectories created in each dir.


LIST WHAT IS ON RECORD

  benchmark.py list [B@R,LxS]

Find entries in the database for the given constraints. Any arguments can
be omitted. (To select only a rev, start with a '@', like '@123'; to select
only spread, start with an 'x', like "x100".)

Call without arguments to get a listing of all available constraints.


COMPARE TIMINGS

  benchmark.py compare B@R,LxS B@R,LxS [B@R,LxS [...]]

Compare any number of timings sets to the first provided set (in text mode).
For example:
  benchmark.py compare 1.7.0 trunk@1349903
    Compare the total timings of all combined '1.7.0' branch runs to
    all combined runs of 'trunk'-at-revision-1349903.
  benchmark.py compare 1.7.0,5x5 trunk@1349903,5x5
    Same as above, but only compare the working copy types with 5 levels
    and a spread of 5.

Use the -c option to limit comparison to specific command names.


SHOW TIMINGS

  benchmark.py show B@R,LxS [B@R,LxS [...]]

Print out a summary of the timings selected from the given constraints.


GENERATE CHARTS

  benchmark.py chart compare B@R,LxS B@R,LxS [ B@R,LxS ... ]

Produce a bar chart that compares any number of sets of timings.  Like with
the plain 'compare' command, the first set is taken as a reference point for
100% and +-0 seconds. Each following dataset produces a set of labeled bar
charts, grouped by svn command names. At least two timings sets must be
provided.

Use the -c option to limit comparison to specific command names.


EXAMPLES

# Run 3 benchmarks on svn 1.7.0 with 5 dir levels and 5 files and subdirs for
# each level (spread). Timings are saved in ./benchmark.db.
# Provide label '1.7.0' and its Last-Changed-Rev for later reference.
./benchmark.py run --svn-bin-dir ~/svn-prefix/1.7.0/bin 1.7.0@1181106,5x5 3

# Record 3 benchmark runs on trunk, again naming its Last-Changed-Rev.
# (You may also set your $PATH instead of using --svn-bin-dir.)
./benchmark.py run --svn-bin-dir ~/svn-prefix/trunk/bin trunk@1352725,5x5 3

# Work with the results of above two runs
./benchmark.py list
./benchmark.py compare 1.7.0 trunk
./benchmark.py show 1.7.0 trunk
./benchmark.py chart compare 1.7.0 trunk
./benchmark.py chart compare 1.7.0 trunk -c "update,commit,TOTAL RUN"

# Rebuild r1352598, run it and chart improvements since 1.7.0.
svn up -r1352598 ~/src/trunk
make -C ~/src/trunk dist-clean install
export PATH="$HOME/svn-prefix/trunk/bin:$PATH"
which svn
./benchmark.py run trunk@1352598,5x5 3
./benchmark.py chart compare 1.7.0 trunk@1352598 trunk@1352725 -o chart.svg


GLOBAL OPTIONS"""

import os
import time
import datetime
import sqlite3
import optparse
import tempfile
import subprocess
import random
import shutil
import stat
import string
from copy import copy

IGNORE_COMMANDS = ('--version', )
TOTAL_RUN = 'TOTAL RUN'

j = os.path.join

def bail(msg=None):
  if msg:
    print(msg)
  exit(1)

def time_str():
  return time.strftime('%Y-%m-%d %H:%M:%S');

def timedelta_to_seconds(td):
  return ( float(td.seconds)
           + float(td.microseconds) / (10**6)
           + td.days * 24 * 60 * 60 )

def run_cmd(cmd, stdin=None, shell=False, verbose=False):
  if options.verbose:
    if shell:
      printable_cmd = cmd
    else:
      printable_cmd = ' '.join(cmd)
    print('CMD:', printable_cmd)

  if stdin:
    stdin_arg = subprocess.PIPE
  else:
    stdin_arg = None

  p = subprocess.Popen(cmd,
                       stdin=stdin_arg,
                       stdout=subprocess.PIPE,
                       stderr=subprocess.PIPE,
                       shell=shell)
  stdout,stderr = p.communicate(input=stdin)

  if verbose:
    if (stdout):
      print("STDOUT: [[[\n%s]]]" % ''.join(stdout))
  if (stderr):
    print("STDERR: [[[\n%s]]]" % ''.join(stderr))

  return stdout, stderr


_next_unique_basename_count = 0

def next_unique_basename(prefix):
  global _next_unique_basename_count
  _next_unique_basename_count += 1
  return '_'.join((prefix, str(_next_unique_basename_count)))


si_units = [
    (1000 ** 5, 'P'),
    (1000 ** 4, 'T'),
    (1000 ** 3, 'G'),
    (1000 ** 2, 'M'),
    (1000 ** 1, 'K'),
    (1000 ** 0, ''),
    ]
def n_label(n):
    """(stolen from hurry.filesize)"""
    for factor, suffix in si_units:
        if n >= factor:
            break
    amount = int(n/factor)
    if isinstance(suffix, tuple):
        singular, multiple = suffix
        if amount == 1:
            suffix = singular
        else:
            suffix = multiple
    return str(amount) + suffix


def split_arg_once(l_r, sep):
  if not l_r:
    return (None, None)
  if sep in l_r:
    l, r = l_r.split(sep)
  else:
    l = l_r
    r = None
  if not l:
    l = None
  if not r:
    r = None
  return (l, r)

RUN_KIND_SEPARATORS=('@', ',', 'x')

class RunKind:
  def __init__(self, b_r_l_s):
    b_r, l_s = split_arg_once(b_r_l_s, RUN_KIND_SEPARATORS[1])
    self.branch, self.revision = split_arg_once(b_r, RUN_KIND_SEPARATORS[0])
    self.levels, self.spread = split_arg_once(l_s, RUN_KIND_SEPARATORS[2])
    if self.levels: self.levels = int(self.levels)
    if self.spread: self.spread = int(self.spread)

  def label(self):
    label_parts = []
    if self.branch:
      label_parts.append(self.branch)
    if self.revision:
      label_parts.append(RUN_KIND_SEPARATORS[0])
      label_parts.append(self.revision)
    if self.levels or self.spread:
      label_parts.append(RUN_KIND_SEPARATORS[1])
      if self.levels:
        label_parts.append(str(self.levels))
      if self.spread:
        label_parts.append(RUN_KIND_SEPARATORS[2])
        label_parts.append(str(self.spread))
    return ''.join(label_parts)

  def args(self):
    return (self.branch, self.revision, self.levels, self.spread)


def parse_timings_selections(db, *args):
  run_kinds = []

  for arg in args:
    run_kind = RunKind(arg)

    if run_kind.revision == 'each':
      run_kind.revision = None
      query = TimingQuery(db, run_kind)
      for revision in query.get_sorted_revisions():
        revision_run_kind = copy(run_kind)
        revision_run_kind.revision = revision
        run_kinds.append(revision_run_kind)
    elif run_kind.revision and run_kind.revision.startswith('last'):
      Nstr = run_kind.revision[4:]
      if not Nstr:
        N = 10
      else:
        N = int(Nstr)
      run_kind.revision = None
      query = TimingQuery(db, run_kind)
      for revision in query.get_sorted_revisions()[-N:]:
        revision_run_kind = copy(run_kind)
        revision_run_kind.revision = revision
        run_kinds.append(revision_run_kind)
    else:
      run_kinds.append(run_kind)

  return run_kinds

def parse_one_timing_selection(db, *args):
  run_kinds = parse_timings_selections(db, *args)
  if len(run_kinds) != 1:
    bail("I need exactly one timings identifier, not '%s'"
         % (' '.join(*args)))
  return run_kinds[0]




PATHNAME_VALID_CHARS = "-_.,@%s%s" % (string.ascii_letters, string.digits)
def filesystem_safe_string(s):
  return ''.join(c for c in s if c in PATHNAME_VALID_CHARS)

def do_div(ref, val):
  if ref:
    return float(val) / float(ref)
  else:
    return 0.0

def do_diff(ref, val):
  return float(val) - float(ref)


# ------------------------- database -------------------------

class TimingsDb:
  def __init__(self, db_path):
    self.db_path = db_path;
    self.conn = sqlite3.connect(db_path)
    self.ensure_tables_created()

  def ensure_tables_created(self):
    c = self.conn.cursor()

    c.execute("""SELECT name FROM sqlite_master WHERE type='table' AND
              name='batch'""")
    if c.fetchone():
      # exists
      return

    print('Creating database tables.')
    c.executescript('''
        CREATE TABLE batch (
          batch_id INTEGER PRIMARY KEY AUTOINCREMENT,
          started TEXT,
          ended TEXT
        );

        CREATE TABLE run_kind (
          run_kind_id INTEGER PRIMARY KEY AUTOINCREMENT,
          branch TEXT NOT NULL,
          revision TEXT NOT NULL,
          wc_levels INTEGER,
          wc_spread INTEGER,
          UNIQUE(branch, revision, wc_levels, wc_spread)
        );

        CREATE TABLE run (
          run_id INTEGER PRIMARY KEY AUTOINCREMENT,
          batch_id INTEGER NOT NULL REFERENCES batch(batch_id),
          run_kind_id INTEGER NOT NULL REFERENCES run_kind(run_kind_id),
          started TEXT,
          ended TEXT,
          aborted INTEGER
        );

        CREATE TABLE timings (
          run_id INTEGER NOT NULL REFERENCES run(run_id),
          command TEXT NOT NULL,
          sequence INTEGER,
          timing REAL
        );'''
      )
    self.conn.commit()
    c.close();


class Batch:
  def __init__(self, db):
    self.db = db
    self.started = time_str()
    c = db.conn.cursor()
    c.execute("INSERT INTO batch (started) values (?)", (self.started,))
    db.conn.commit()
    self.id = c.lastrowid
    c.close()

  def done(self):
    conn = self.db.conn
    c = conn.cursor()
    c.execute("""
        UPDATE batch
        SET ended = ?
        WHERE batch_id = ?""",
        (time_str(), self.id))
    conn.commit()
    c.close()

class Run:
  def __init__(self, batch, run_kind):
    self.batch = batch
    conn = self.batch.db.conn
    c = conn.cursor()

    c.execute("""
        SELECT run_kind_id FROM run_kind
        WHERE branch = ?
          AND revision = ?
          AND wc_levels = ?
          AND wc_spread = ?""",
        run_kind.args())
    kind_ids = c.fetchone()
    if kind_ids:
      kind_id = kind_ids[0]
    else:
      c.execute("""
          INSERT INTO run_kind (branch, revision, wc_levels, wc_spread)
          VALUES (?, ?, ?, ?)""",
          run_kind.args())
      conn.commit()
      kind_id = c.lastrowid

    self.started = time_str()

    c.execute("""
        INSERT INTO run
          (batch_id, run_kind_id, started)
        VALUES
          (?, ?, ?)""",
        (self.batch.id, kind_id, self.started))
    conn.commit()
    self.id = c.lastrowid
    c.close();
    self.tic_at = None
    self.current_command = None
    self.timings = []

  def tic(self, command):
    if command in IGNORE_COMMANDS:
      return
    self.toc()
    self.current_command = command
    self.tic_at = datetime.datetime.now()

  def toc(self):
    if self.current_command and self.tic_at:
      toc_at = datetime.datetime.now()
      self.remember_timing(self.current_command,
                         timedelta_to_seconds(toc_at - self.tic_at))
    self.current_command = None
    self.tic_at = None

  def remember_timing(self, command, seconds):
    self.timings.append((command, seconds))

  def submit_timings(self):
    conn = self.batch.db.conn
    c = conn.cursor()
    print('submitting...')

    c.executemany("""
      INSERT INTO timings
        (run_id, command, sequence, timing)
      VALUES
        (?, ?, ?, ?)""",
      [(self.id, t[0], (i + 1), t[1]) for i,t in enumerate(self.timings)])

    conn.commit()
    c.close()

  def done(self, aborted=False):
    conn = self.batch.db.conn
    c = conn.cursor()
    c.execute("""
        UPDATE run
        SET ended = ?, aborted = ?
        WHERE run_id = ?""",
        (time_str(), aborted, self.id))
    conn.commit()
    c.close()


class TimingQuery:
  def __init__(self, db, run_kind):
    self.cursor = db.conn.cursor()
    self.constraints = []
    self.values = []
    self.timings = None
    self.FROM_WHERE = """
         FROM batch AS b,
              timings AS t,
              run AS r,
              run_kind as k
         WHERE
              t.run_id = r.run_id
              AND k.run_kind_id = r.run_kind_id
              AND b.batch_id = r.batch_id
              AND r.aborted = 0
         """
    self.append_constraint('k.branch', run_kind.branch)
    self.each_revision = False
    if run_kind.revision == 'each':
      self.each_revision = True
    else:
      self.append_constraint('k.revision', run_kind.revision)
    self.append_constraint('k.wc_levels', run_kind.levels)
    self.append_constraint('k.wc_spread', run_kind.spread)
    self.label = run_kind.label()

  def append_constraint(self, column_name, val):
    if val:
      self.constraints.append('AND %s = ?' % column_name)
      self.values.append(val)

  def remove_last_constraint(self):
    del self.constraints[-1]
    del self.values[-1]

  def get_sorted_X(self, x, n=1):
    query = ['SELECT DISTINCT %s' % x,
             self.FROM_WHERE ]
    query.extend(self.constraints)
    query.append('ORDER BY %s' % x)
    c = db.conn.cursor()
    try:
      c.execute(' '.join(query), self.values)
      if n == 1:
        return [tpl[0] for tpl in c.fetchall()]
      else:
        return c.fetchall()
    finally:
      c.close()

  def get_sorted_command_names(self):
    return self.get_sorted_X('t.command')

  def get_sorted_branches(self):
    return self.get_sorted_X('k.branch')

  def get_sorted_revisions(self):
    return self.get_sorted_X('k.revision')

  def get_sorted_levels_spread(self):
    return self.get_sorted_X('k.wc_levels,k.wc_spread', n = 2)

  def count_runs_batches(self):
    query = ["""SELECT
                  count(DISTINCT r.run_id),
                  count(DISTINCT b.batch_id)""",
             self.FROM_WHERE ]
    query.extend(self.constraints)
    c = db.conn.cursor()
    try:
      #print ' '.join(query)
      c.execute(' '.join(query), self.values)
      return c.fetchone()
    finally:
      c.close()

  def get_command_timings(self, command):
    query = ["""SELECT
                  count(t.timing),
                  min(t.timing),
                  max(t.timing),
                  avg(t.timing)""",
             self.FROM_WHERE ]
    self.append_constraint('t.command', command)
    try:
      query.extend(self.constraints)
      c = db.conn.cursor()
      try:
        c.execute(' '.join(query), self.values)
        return c.fetchone()
      finally:
        c.close()
    finally:
      self.remove_last_constraint()

  def get_timings(self):
    if self.timings:
      return self.timings
    self.timings = {}
    for command_name in self.get_sorted_command_names():
      self.timings[command_name] = self.get_command_timings(command_name)
    return self.timings


# ------------------------------------------------------------ run tests


def perform_run(batch, run_kind,
                svn_bin, svnadmin_bin, verbose):

  run = Run(batch, run_kind)

  def create_tree(in_dir, _levels, _spread):
    try:
      os.mkdir(in_dir)
    except:
      pass

    for i in range(_spread):
      # files
      fn = j(in_dir, next_unique_basename('file'))
      f = open(fn, 'w')
      f.write('This is %s\n' % fn)
      f.close()

      # dirs
      if (_levels > 1):
        dn = j(in_dir, next_unique_basename('dir'))
        create_tree(dn, _levels - 1, _spread)

  def svn(*args):
    name = args[0]

    cmd = [ svn_bin ]
    cmd.extend( list(args) )
    if verbose:
      print('svn cmd:', ' '.join(cmd))

    stdin = None
    if stdin:
      stdin_arg = subprocess.PIPE
    else:
      stdin_arg = None

    run.tic(name)
    try:
      p = subprocess.Popen(cmd,
                           stdin=stdin_arg,
                           stdout=subprocess.PIPE,
                           stderr=subprocess.PIPE,
                           shell=False)
      stdout,stderr = p.communicate(input=stdin)
    except OSError:
      stdout = stderr = None
    finally:
      run.toc()

    if verbose:
      if (stdout):
        print("STDOUT: [[[\n%s]]]" % ''.join(stdout))
      if (stderr):
        print("STDERR: [[[\n%s]]]" % ''.join(stderr))

    return stdout,stderr


  def add(*args):
    return svn('add', *args)

  def ci(*args):
    return svn('commit', '-mm', *args)

  def up(*args):
    return svn('update', *args)

  def st(*args):
    return svn('status', *args)

  def info(*args):
    return svn('info', *args)

  _chars = [chr(x) for x in range(ord('a'), ord('z') +1)]

  def randstr(len=8):
    return ''.join( [random.choice(_chars) for i in range(len)] )

  def _copy(path):
    dest = next_unique_basename(path + '_copied')
    svn('copy', path, dest)

  def _move(path):
    dest = path + '_moved'
    svn('move', path, dest)

  def _propmod(path):
    so, se = svn('proplist', path)
    propnames = [line.strip() for line in so.strip().split('\n')[1:]]

    # modify?
    if len(propnames):
      svn('ps', propnames[len(propnames) / 2], randstr(), path)

    # del?
    if len(propnames) > 1:
      svn('propdel', propnames[len(propnames) / 2], path)

  def _propadd(path):
    # set a new one.
    svn('propset', randstr(), randstr(), path)

  def _mod(path):
    if os.path.isdir(path):
      _propmod(path)
      return

    f = open(path, 'a')
    f.write('\n%s\n' % randstr())
    f.close()

  def _add(path):
    if os.path.isfile(path):
      return _mod(path)

    if random.choice((True, False)):
      # create a dir
      svn('mkdir', j(path, next_unique_basename('new_dir')))
    else:
      # create a file
      new_path = j(path, next_unique_basename('new_file'))
      f = open(new_path, 'w')
      f.write(randstr())
      f.close()
      svn('add', new_path)

  def _del(path):
    svn('delete', path)

  _mod_funcs = (_mod, _add, _propmod, _propadd, )#_copy,) # _move, _del)

  def modify_tree(in_dir, fraction):
    child_names = os.listdir(in_dir)
    for child_name in child_names:
      if child_name[0] == '.':
        continue
      if random.random() < fraction:
        path = j(in_dir, child_name)
        random.choice(_mod_funcs)(path)

    for child_name in child_names:
      if child_name[0] == '.': continue
      path = j(in_dir, child_name)
      if os.path.isdir(path):
        modify_tree(path, fraction)

  def propadd_tree(in_dir, fraction):
    for child_name in os.listdir(in_dir):
      if child_name[0] == '.': continue
      path = j(in_dir, child_name)
      if random.random() < fraction:
        _propadd(path)
      if os.path.isdir(path):
        propadd_tree(path, fraction)


  def rmtree_onerror(func, path, exc_info):
    """Error handler for ``shutil.rmtree``.

    If the error is due to an access error (read only file)
    it attempts to add write permission and then retries.

    If the error is for another reason it re-raises the error.

    Usage : ``shutil.rmtree(path, onerror=onerror)``
    """
    if not os.access(path, os.W_OK):
      # Is the error an access error ?
      os.chmod(path, stat.S_IWUSR)
      func(path)
    else:
      raise

  base = tempfile.mkdtemp()

  # ensure identical modifications for every run
  random.seed(0)

  aborted = True

  try:
    repos = j(base, 'repos')
    repos = repos.replace('\\', '/')
    wc = j(base, 'wc')
    wc2 = j(base, 'wc2')

    if repos.startswith('/'):
      file_url = 'file://%s' % repos
    else:
      file_url = 'file:///%s' % repos

    print('\nRunning svn benchmark in', base)
    print('dir levels: %s; new files and dirs per leaf: %s' %(
          run_kind.levels, run_kind.spread))

    started = datetime.datetime.now()

    try:
      run_cmd([svnadmin_bin, 'create', repos])
      svn('checkout', file_url, wc)

      trunk = j(wc, 'trunk')
      create_tree(trunk, run_kind.levels, run_kind.spread)
      add(trunk)
      st(wc)
      ci(wc)
      up(wc)
      propadd_tree(trunk, 0.05)
      ci(wc)
      up(wc)
      st(wc)
      info('-R', wc)

      trunk_url = file_url + '/trunk'
      branch_url = file_url + '/branch'

      svn('copy', '-mm', trunk_url, branch_url)
      st(wc)

      up(wc)
      st(wc)
      info('-R', wc)

      svn('checkout', trunk_url, wc2)
      st(wc2)
      modify_tree(wc2, 0.5)
      st(wc2)
      ci(wc2)
      up(wc2)
      up(wc)

      svn('switch', branch_url, wc2)
      modify_tree(wc2, 0.5)
      st(wc2)
      info('-R', wc2)
      ci(wc2)
      up(wc2)
      up(wc)

      modify_tree(trunk, 0.5)
      st(wc)
      ci(wc)
      up(wc2)
      up(wc)

      svn('merge', '--accept=postpone', trunk_url, wc2)
      st(wc2)
      info('-R', wc2)
      svn('resolve', '--accept=mine-conflict', wc2)
      st(wc2)
      svn('resolved', '-R', wc2)
      st(wc2)
      info('-R', wc2)
      ci(wc2)
      up(wc2)
      up(wc)

      svn('merge', '--accept=postpone', '--reintegrate', branch_url, trunk)
      st(wc)
      svn('resolve', '--accept=mine-conflict', wc)
      st(wc)
      svn('resolved', '-R', wc)
      st(wc)
      ci(wc)
      up(wc2)
      up(wc)

      svn('delete', j(wc, 'branch'))
      ci(wc)
      up(wc)

      aborted = False

    finally:
      stopped = datetime.datetime.now()
      print('\nDone with svn benchmark in', (stopped - started))

      run.remember_timing(TOTAL_RUN,
                        timedelta_to_seconds(stopped - started))
  finally:
    run.done(aborted)
    run.submit_timings()
    shutil.rmtree(base, onerror=rmtree_onerror)

  return aborted


# ---------------------------------------------------------------------


def cmdline_run(db, options, run_kind_str, N=1):
  run_kind = parse_one_timing_selection(db, run_kind_str)

  N = int(N)

  print('Hi, going to run a Subversion benchmark series of %d runs...' % N)
  print('Label is %s' % run_kind.label())

  # can we run the svn binaries?
  svn_bin = j(options.svn_bin_dir, 'svn')
  svnadmin_bin = j(options.svn_bin_dir, 'svnadmin')

  for b in (svn_bin, svnadmin_bin):
    so,se = run_cmd([b, '--version'])
    if not so:
      bail("Can't run %s" % b)

    print(', '.join([s.strip() for s in so.split('\n')[:2]]))

  batch = Batch(db)

  for i in range(N):
    print('Run %d of %d' % (i + 1, N))
    perform_run(batch, run_kind,
                svn_bin, svnadmin_bin, options.verbose)

  batch.done()


def cmdline_list(db, options, *args):
  run_kinds = parse_timings_selections(db, *args)

  for run_kind in run_kinds:

    constraints = []
    def add_if_not_none(name, val):
      if val:
        constraints.append('  %s = %s' % (name, val))
    add_if_not_none('branch', run_kind.branch)
    add_if_not_none('revision', run_kind.revision)
    add_if_not_none('levels', run_kind.levels)
    add_if_not_none('spread', run_kind.spread)
    if constraints:
      print('For\n', '\n'.join(constraints))
    print('I found:')

    d = TimingQuery(db, run_kind)

    cmd_names = d.get_sorted_command_names()
    if cmd_names:
      print('\n%d command names:\n ' % len(cmd_names), '\n  '.join(cmd_names))

    branches = d.get_sorted_branches()
    if branches and (len(branches) > 1 or branches[0] != run_kind.branch):
      print('\n%d branches:\n ' % len(branches), '\n  '.join(branches))

    revisions = d.get_sorted_revisions()
    if revisions and (len(revisions) > 1 or revisions[0] != run_kind.revision):
      print('\n%d revisions:\n ' % len(revisions), '\n  '.join(revisions))

    levels_spread = d.get_sorted_levels_spread()
    if levels_spread and (
         len(levels_spread) > 1
         or levels_spread[0] != (run_kind.levels, run_kind.spread)):
      print('\n%d kinds of levels x spread:\n ' % len(levels_spread), '\n  '.join(
              [ ('%dx%d' % (l, s)) for l,s in levels_spread ]))

    print("\n%d runs in %d batches.\n" % (d.count_runs_batches()))


def cmdline_show(db, options, *run_kind_strings):
  run_kinds = parse_timings_selections(db, *run_kind_strings)
  for run_kind in run_kinds:
    q = TimingQuery(db, run_kind)
    timings = q.get_timings()

    s = []
    s.append('Timings for %s' % run_kind.label())
    s.append('   N    min     max     avg   operation  (unit is seconds)')

    for command_name in q.get_sorted_command_names():
      if options.command_names and command_name not in options.command_names:
        continue
      n, tmin, tmax, tavg = timings[command_name]

      s.append('%4s %7.2f %7.2f %7.2f  %s' % (
                 n_label(n),
                 tmin,
                 tmax,
                 tavg,
                 command_name))

    print('\n'.join(s))


def cmdline_compare(db, options, *args):
  run_kinds = parse_timings_selections(db, *args)
  if len(run_kinds) < 2:
    bail("Need at least two sets of timings to compare.")


  left_kind = run_kinds[0]
  leftq = TimingQuery(db, left_kind)
  left = leftq.get_timings()
  if not left:
    bail("No timings for %s" % left_kind.label())

  for run_kind_idx in range(1, len(run_kinds)):
    right_kind = run_kinds[run_kind_idx]

    rightq = TimingQuery(db, right_kind)
    right = rightq.get_timings()
    if not right:
      print("No timings for %s" % right_kind.label())
      continue

    label = 'Compare %s to %s' % (right_kind.label(), left_kind.label())

    s = [label]

    verbose = options.verbose
    if not verbose:
      s.append('       N        avg         operation')
    else:
      s.append('       N        min              max              avg         operation')

    command_names = [name for name in leftq.get_sorted_command_names()
                     if name in right]
    if options.command_names:
      command_names = [name for name in command_names
                       if name in options.command_names]

    for command_name in command_names:
      left_N, left_min, left_max, left_avg = left[command_name]
      right_N, right_min, right_max, right_avg = right[command_name]

      N_str = '%s/%s' % (n_label(left_N), n_label(right_N))
      avg_str = '%7.2f|%+7.3f' % (do_div(left_avg, right_avg),
                                  do_diff(left_avg, right_avg))

      if not verbose:
        s.append('%9s %-16s  %s' % (N_str, avg_str, command_name))
      else:
        min_str = '%7.2f|%+7.3f' % (do_div(left_min, right_min),
                                    do_diff(left_min, right_min))
        max_str = '%7.2f|%+7.3f' % (do_div(left_max, right_max),
                                    do_diff(left_max, right_max))

        s.append('%9s %-16s %-16s %-16s  %s' % (N_str, min_str, max_str, avg_str,
                                            command_name))

    s.extend([
      '(legend: "1.23|+0.45" means: slower by factor 1.23 and by 0.45 seconds;',
      ' factor < 1 and seconds < 0 means \'%s\' is faster.'
      % right_kind.label(),
      ' "2/3" means: \'%s\' has 2 timings on record, the other has 3.)'
      % left_kind.label()
      ])


    print('\n'.join(s))


# ------------------------------------------------------- charts

def cmdline_chart_compare(db, options, *args):
  import matplotlib
  matplotlib.use('Agg')
  import numpy as np
  import matplotlib.pylab as plt

  labels = []
  timing_sets = []
  command_names = None

  run_kinds = parse_timings_selections(db, *args)

  # iterate the timings selections and accumulate data
  for run_kind in run_kinds:
    query = TimingQuery(db, run_kind)
    timings = query.get_timings()
    if not timings:
      print("No timings for %s" % run_kind.label())
      continue
    labels.append(run_kind.label())
    timing_sets.append(timings)

    # it only makes sense to compare those commands that have timings
    # in the first selection, because that is the one everything else
    # is compared to. Remember the first selection's command names.
    if not command_names:
      command_names = query.get_sorted_command_names()


  if len(timing_sets) < 2:
    bail("Not enough timings")

  if options.command_names:
    command_names = [name for name in command_names
                     if name in options.command_names]

  chart_path = options.chart_path
  if not chart_path:
    chart_path = 'compare_' + '_'.join(
      [ filesystem_safe_string(l) for l in labels ]
      ) + '.svg'

  N = len(command_names)
  M = len(timing_sets) - 1
  if M < 2:
    M = 2

  group_positions = np.arange(N)  # the y locations for the groups
  dist = 1. / (1. + M)
  height = (1. - dist) / M     # the height of the bars

  fig = plt.figure(figsize=(12, 5 + 0.2*N*M))
  plot1 = fig.add_subplot(121)
  plot2 = fig.add_subplot(122)

  left = timing_sets[0]

  # Iterate timing sets. Each loop produces one bar for each command name
  # group.
  for label_i,label in enumerate(labels[1:],1):
    right = timing_sets[label_i]
    if not right:
      continue

    for cmd_i, command_name in enumerate(command_names):
      if command_name not in right:
        #skip
        continue

      left_N, left_min, left_max, left_avg = left[command_name]
      right_N, right_min, right_max, right_avg = right[command_name]

      div_avg = 100. * (do_div(left_avg, right_avg) - 1.0)
      if div_avg <= 0:
        col = '#55dd55'
      else:
        col = '#dd5555'

      diff_val = do_diff(left_avg, right_avg)

      ofs = (dist + height) / 2. + height * (label_i - 1)

      barheight = height * (1.0 - dist)

      y = float(cmd_i) + ofs

      plot1.barh((y, ),
                 (div_avg, ),
                 barheight,
                 color=col, edgecolor='white')
      plot1.text(0., y + height/2.,
                 '%s %+5.1f%%' % (label, div_avg),
                 ha='right', va='center', size='small',
                 rotation=0, family='monospace')

      plot2.barh((y, ),
                 (diff_val, ),
                 barheight,
                 color=col, edgecolor='white')
      plot2.text(0., y + height/2.,
                 '%s %+6.2fs' % (label, diff_val),
                 ha='right', va='center', size='small',
                 rotation=0, family='monospace')


  for p in (plot1, plot2):
    xlim = list(p.get_xlim())
    if xlim[1] < 10.:
      xlim[1] = 10.
    # make sure the zero line is far enough right so that the annotations
    # fit inside the chart. About half the width should suffice.
    if xlim[0] > -xlim[1]:
      xlim[0] = -xlim[1]
    p.set_xlim(*xlim)
    p.set_xticks((0,))
    p.set_yticks(group_positions + (height / 2.))
    p.set_yticklabels(())
    p.set_ylim((len(command_names), 0))
    p.grid()

  plot1.set_xticklabels(('+-0%',), rotation=0)
  plot1.set_title('Average runtime change from %s in %%' % labels[0],
                  size='medium')

  plot2.set_xticklabels(('+-0s',), rotation=0)
  plot2.set_title('Average runtime change from %s in seconds' % labels[0],
                  size='medium')

  margin = 1./(2 + N*M)
  titlemargin = 0
  if options.title:
    titlemargin = margin * 1.5

  fig.subplots_adjust(left=0.005, right=0.995, wspace=0.3, bottom=margin,
                      top=1.0-margin-titlemargin)

  ystep = (1.0 - 2.*margin - titlemargin) / len(command_names)

  for idx,command_name in enumerate(command_names):
    ylabel = '%s\nvs. %.1fs' % (
                     command_name,
                     left[command_name][3])

    ypos=1.0 - margin - titlemargin - ystep/M - ystep * idx
    plt.figtext(0.5, ypos,
                command_name,
                ha='center', va='top',
                size='medium', weight='bold')
    plt.figtext(0.5, ypos - ystep/(M+1),
                '%s\n= %.2fs' % (
                  labels[0], left[command_name][3]),
                ha='center', va='top',
                size='small')

  if options.title:
    plt.figtext(0.5, 1. - titlemargin/2, options.title, ha='center',
                va='center', weight='bold')

  plt.savefig(chart_path)
  print('wrote chart file:', chart_path)


# ------------------------------------------------------------ main


# Custom option formatter, keeping newlines in the description.
# adapted from:
# http://groups.google.com/group/comp.lang.python/msg/09f28e26af0699b1
import textwrap
class IndentedHelpFormatterWithNL(optparse.IndentedHelpFormatter):
  def format_description(self, description):
    if not description: return ""
    desc_width = self.width - self.current_indent
    indent = " "*self.current_indent
    bits = description.split('\n')
    formatted_bits = [
      textwrap.fill(bit,
        desc_width,
        initial_indent=indent,
        subsequent_indent=indent)
      for bit in bits]
    result = "\n".join(formatted_bits) + "\n"
    return result

if __name__ == '__main__':
  parser = optparse.OptionParser(formatter=IndentedHelpFormatterWithNL())
  # -h is automatically added.
  ### should probably expand the help for that. and see about -?
  parser.add_option('-v', '--verbose', action='store_true', dest='verbose',
                    help='Verbose operation')
  parser.add_option('-b', '--svn-bin-dir', action='store', dest='svn_bin_dir',
                    default='',
                    help='Specify directory to find Subversion binaries in')
  parser.add_option('-f', '--db-path', action='store', dest='db_path',
                    default='benchmark.db',
                    help='Specify path to SQLite database file')
  parser.add_option('-o', '--chart-path', action='store', dest='chart_path',
                    help='Supply a path for chart output.')
  parser.add_option('-c', '--command-names', action='store',
                    dest='command_names',
                    help='Comma separated list of command names to limit to.')
  parser.add_option('-t', '--title', action='store',
                    dest='title',
                    help='For charts, a title to print in the chart graphics.')

  parser.set_description(__doc__)
  parser.set_usage('')


  options, args = parser.parse_args()

  def usage(msg=None):
    parser.print_help()
    if msg:
      print("")
      print(msg)
    bail()

  # there should be at least one arg left: the sub-command
  if not args:
    usage('No command argument supplied.')

  cmd = args[0]
  del args[0]

  db = TimingsDb(options.db_path)

  if cmd == 'run':
    if len(args) < 1 or len(args) > 2:
      usage()
    cmdline_run(db, options, *args)

  elif cmd == 'compare':
    if len(args) < 2:
      usage()
    cmdline_compare(db, options, *args)

  elif cmd == 'list':
    cmdline_list(db, options, *args)

  elif cmd == 'show':
    cmdline_show(db, options, *args)

  elif cmd == 'chart':
    if 'compare'.startswith(args[0]):
      cmdline_chart_compare(db, options, *args[1:])
    else:
      usage()

  else:
    usage('Unknown subcommand argument: %s' % cmd)