contrib/compare_two_ftime_report_sets

   1 #!/usr/bin/python
   2
   3 # Script to statistically compare two sets of log files with -ftime-report
   4 # output embedded within them.
   5
   6 # Contributed by Lawrence Crowl <crowl@google.com>
   7 #
   8 # Copyright (C) 2012-2024 Free Software Foundation, Inc.
   9 #
  10 # This file is part of GCC.
  11 #
  12 # GCC is free software; you can redistribute it and/or modify
  13 # it under the terms of the GNU General Public License as published by
  14 # the Free Software Foundation; either version 3, or (at your option)
  15 # any later version.
  16 #
  17 # GCC is distributed in the hope that it will be useful,
  18 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 # GNU General Public License for more details.
  21 #
  22 # You should have received a copy of the GNU General Public License
  23 # along with GCC; see the file COPYING.  If not, write to
  24 # the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  25 # Boston, MA 02110-1301, USA.
  26
  27
  28 """ Compare two sets of compile-time performance numbers.
  29
  30 The intent of this script is to compare compile-time performance of two
  31 different versions of the compiler.  Each version of the compiler must be
  32 run at least three times with the -ftime-report option.  Each log file
  33 represents a data point, or trial.  The set of trials for each compiler
  34 version constitutes a sample.  The ouput of the script is a description
  35 of the statistically significant difference between the two version of
  36 the compiler.
  37
  38 The parameters to the script are:
  39
  40   Two file patterns that each match a set of log files.  You will probably
  41   need to quote the patterns before passing them to the script.
  42
  43     Each pattern corresponds to a version of the compiler.
  44
  45   A regular expression that finds interesting lines in the log files.
  46   If you want to match the beginning of the line, you will need to add
  47   the ^ operator.  The filtering uses Python regular expression syntax.
  48
  49     The default is "TOTAL".
  50
  51     All of the interesting lines in a single log file are summed to produce
  52     a single trial (data point).
  53
  54   A desired statistical confidence within the range 60% to 99.9%.  Due to
  55   the implementation, this confidence will be rounded down to one of 60%,
  56   70%, 80%, 90%, 95%, 98%, 99%, 99.5%, 99.8%, and 99.9%.
  57
  58     The default is 95.
  59
  60     If the computed confidence is lower than desired, the script will
  61     estimate the number of trials needed to meet the desired confidence.
  62     This estimate is not very good, as the variance tends to change as
  63     you increase the number of trials.
  64
  65 The most common use of the script is total compile-time comparison between
  66 logfiles stored in different directories.
  67
  68 compare_two_ftime_report_sets "Log1/*perf" "Log2/*perf"
  69
  70 One can also look at parsing time, but expecting a lower confidence.
  71
  72 compare_two_ftime_report_sets "Log1/*perf" "Log2/*perf" "^phase parsing" 75
  73
  74 """
  75
  76
  77 import os
  78 import sys
  79 import fnmatch
  80 import glob
  81 import re
  82 import math
  83
  84
  85 ####################################################################### Utility
  86
  87
  88 def divide(dividend, divisor):
  89   """ Return the quotient, avoiding division by zero.
  90   """
  91   if divisor == 0:
  92     return sys.float_info.max
  93   else:
  94     return dividend / divisor
  95
  96
  97 ################################################################# File and Line
  98
  99
 100 # Should you repurpose this script, this code might help.
 101 #
 102 #def find_files(topdir, filepat):
 103 #  """ Find a set of file names, under a given directory,
 104 #  matching a Unix shell file pattern.
 105 #  Returns an iterator over the file names.
 106 #  """
 107 #  for path, dirlist, filelist in os.walk(topdir):
 108 #    for name in fnmatch.filter(filelist, filepat):
 109 #      yield os.path.join(path, name)
 110
 111
 112 def match_files(fileglob):
 113   """ Find a set of file names matching a Unix shell glob pattern.
 114   Returns an iterator over the file names.
 115   """
 116   return glob.iglob(os.path.expanduser(fileglob))
 117
 118
 119 def lines_in_file(filename):
 120   """ Return an iterator over lines in the named file.  """
 121   filedesc = open(filename, "r")
 122   for line in filedesc:
 123     yield line
 124   filedesc.close()
 125
 126
 127 def lines_containing_pattern(pattern, lines):
 128   """ Find lines by a Python regular-expression.
 129   Returns an iterator over lines containing the expression.
 130   """
 131   parser = re.compile(pattern)
 132   for line in lines:
 133     if parser.search(line):
 134       yield line
 135
 136
 137 ############################################################# Number Formatting
 138
 139
 140 def strip_redundant_digits(numrep):
 141   if numrep.find(".") == -1:
 142     return numrep
 143   return numrep.rstrip("0").rstrip(".")
 144
 145
 146 def text_number(number):
 147   return strip_redundant_digits("%g" % number)
 148
 149
 150 def round_significant(digits, number):
 151   if number == 0:
 152     return 0
 153   magnitude = abs(number)
 154   significance = math.floor(math.log10(magnitude))
 155   least_position = int(significance - digits + 1)
 156   return round(number, -least_position)
 157
 158
 159 def text_significant(digits, number):
 160   return text_number(round_significant(digits, number))
 161
 162
 163 def text_percent(number):
 164   return text_significant(3, number*100) + "%"
 165
 166
 167 ################################################################ T-Distribution
 168
 169
 170 # This section of code provides functions for using Student's t-distribution.
 171
 172
 173 # The functions are implemented using table lookup
 174 # to facilitate implementation of inverse functions.
 175
 176
 177 # The table is comprised of row 0 listing the alpha values,
 178 # column 0 listing the degree-of-freedom values,
 179 # and the other entries listing the corresponding t-distribution values.
 180
 181 t_dist_table = [
 182 [  0, 0.200, 0.150, 0.100, 0.050, 0.025, 0.010, 0.005, .0025, 0.001, .0005],
 183 [  1, 1.376, 1.963, 3.078, 6.314, 12.71, 31.82, 63.66, 127.3, 318.3, 636.6],
 184 [  2, 1.061, 1.386, 1.886, 2.920, 4.303, 6.965, 9.925, 14.09, 22.33, 31.60],
 185 [  3, 0.978, 1.250, 1.638, 2.353, 3.182, 4.541, 5.841, 7.453, 10.21, 12.92],
 186 [  4, 0.941, 1.190, 1.533, 2.132, 2.776, 3.747, 4.604, 5.598, 7.173, 8.610],
 187 [  5, 0.920, 1.156, 1.476, 2.015, 2.571, 3.365, 4.032, 4.773, 5.894, 6.869],
 188 [  6, 0.906, 1.134, 1.440, 1.943, 2.447, 3.143, 3.707, 4.317, 5.208, 5.959],
 189 [  7, 0.896, 1.119, 1.415, 1.895, 2.365, 2.998, 3.499, 4.029, 4.785, 5.408],
 190 [  8, 0.889, 1.108, 1.397, 1.860, 2.306, 2.896, 3.355, 3.833, 4.501, 5.041],
 191 [  9, 0.883, 1.100, 1.383, 1.833, 2.262, 2.821, 3.250, 3.690, 4.297, 4.781],
 192 [ 10, 0.879, 1.093, 1.372, 1.812, 2.228, 2.764, 3.169, 3.581, 4.144, 4.587],
 193 [ 11, 0.876, 1.088, 1.363, 1.796, 2.201, 2.718, 3.106, 3.497, 4.025, 4.437],
 194 [ 12, 0.873, 1.083, 1.356, 1.782, 2.179, 2.681, 3.055, 3.428, 3.930, 4.318],
 195 [ 13, 0.870, 1.079, 1.350, 1.771, 2.160, 2.650, 3.012, 3.372, 3.852, 4.221],
 196 [ 14, 0.868, 1.076, 1.345, 1.761, 2.145, 2.624, 2.977, 3.326, 3.787, 4.140],
 197 [ 15, 0.866, 1.074, 1.341, 1.753, 2.131, 2.602, 2.947, 3.286, 3.733, 4.073],
 198 [ 16, 0.865, 1.071, 1.337, 1.746, 2.120, 2.583, 2.921, 3.252, 3.686, 4.015],
 199 [ 17, 0.863, 1.069, 1.333, 1.740, 2.110, 2.567, 2.898, 3.222, 3.646, 3.965],
 200 [ 18, 0.862, 1.067, 1.330, 1.734, 2.101, 2.552, 2.878, 3.197, 3.610, 3.922],
 201 [ 19, 0.861, 1.066, 1.328, 1.729, 2.093, 2.539, 2.861, 3.174, 3.579, 3.883],
 202 [ 20, 0.860, 1.064, 1.325, 1.725, 2.086, 2.528, 2.845, 3.153, 3.552, 3.850],
 203 [ 21, 0.859, 1.063, 1.323, 1.721, 2.080, 2.518, 2.831, 3.135, 3.527, 3.819],
 204 [ 22, 0.858, 1.061, 1.321, 1.717, 2.074, 2.508, 2.819, 3.119, 3.505, 3.792],
 205 [ 23, 0.858, 1.060, 1.319, 1.714, 2.069, 2.500, 2.807, 3.104, 3.485, 3.768],
 206 [ 24, 0.857, 1.059, 1.318, 1.711, 2.064, 2.492, 2.797, 3.091, 3.467, 3.745],
 207 [ 25, 0.856, 1.058, 1.316, 1.708, 2.060, 2.485, 2.787, 3.078, 3.450, 3.725],
 208 [ 26, 0.856, 1.058, 1.315, 1.706, 2.056, 2.479, 2.779, 3.067, 3.435, 3.707],
 209 [ 27, 0.855, 1.057, 1.314, 1.703, 2.052, 2.473, 2.771, 3.057, 3.421, 3.689],
 210 [ 28, 0.855, 1.056, 1.313, 1.701, 2.048, 2.467, 2.763, 3.047, 3.408, 3.674],
 211 [ 29, 0.854, 1.055, 1.311, 1.699, 2.045, 2.462, 2.756, 3.038, 3.396, 3.660],
 212 [ 30, 0.854, 1.055, 1.310, 1.697, 2.042, 2.457, 2.750, 3.030, 3.385, 3.646],
 213 [ 31, 0.853, 1.054, 1.309, 1.696, 2.040, 2.453, 2.744, 3.022, 3.375, 3.633],
 214 [ 32, 0.853, 1.054, 1.309, 1.694, 2.037, 2.449, 2.738, 3.015, 3.365, 3.622],
 215 [ 33, 0.853, 1.053, 1.308, 1.692, 2.035, 2.445, 2.733, 3.008, 3.356, 3.611],
 216 [ 34, 0.852, 1.052, 1.307, 1.691, 2.032, 2.441, 2.728, 3.002, 3.348, 3.601],
 217 [ 35, 0.852, 1.052, 1.306, 1.690, 2.030, 2.438, 2.724, 2.996, 3.340, 3.591],
 218 [ 36, 0.852, 1.052, 1.306, 1.688, 2.028, 2.434, 2.719, 2.990, 3.333, 3.582],
 219 [ 37, 0.851, 1.051, 1.305, 1.687, 2.026, 2.431, 2.715, 2.985, 3.326, 3.574],
 220 [ 38, 0.851, 1.051, 1.304, 1.686, 2.024, 2.429, 2.712, 2.980, 3.319, 3.566],
 221 [ 39, 0.851, 1.050, 1.304, 1.685, 2.023, 2.426, 2.708, 2.976, 3.313, 3.558],
 222 [ 40, 0.851, 1.050, 1.303, 1.684, 2.021, 2.423, 2.704, 2.971, 3.307, 3.551],
 223 [ 50, 0.849, 1.047, 1.299, 1.676, 2.009, 2.403, 2.678, 2.937, 3.261, 3.496],
 224 [ 60, 0.848, 1.045, 1.296, 1.671, 2.000, 2.390, 2.660, 2.915, 3.232, 3.460],
 225 [ 80, 0.846, 1.043, 1.292, 1.664, 1.990, 2.374, 2.639, 2.887, 3.195, 3.416],
 226 [100, 0.845, 1.042, 1.290, 1.660, 1.984, 2.364, 2.626, 2.871, 3.174, 3.390],
 227 [150, 0.844, 1.040, 1.287, 1.655, 1.976, 2.351, 2.609, 2.849, 3.145, 3.357] ]
 228
 229
 230 # The functions use the following parameter name conventions:
 231 # alpha - the alpha parameter
 232 # degree - the degree-of-freedom parameter
 233 # value - the t-distribution value for some alpha and degree
 234 # deviations - a confidence interval radius,
 235 #   expressed as a multiple of the standard deviation of the sample
 236 # ax - the alpha parameter index
 237 # dx - the degree-of-freedom parameter index
 238
 239 # The interface to this section of code is the last three functions,
 240 # find_t_dist_value, find_t_dist_alpha, and find_t_dist_degree.
 241
 242
 243 def t_dist_alpha_at_index(ax):
 244   if ax == 0:
 245     return .25 # effectively no confidence
 246   else:
 247     return t_dist_table[0][ax]
 248
 249
 250 def t_dist_degree_at_index(dx):
 251   return t_dist_table[dx][0]
 252
 253
 254 def t_dist_value_at_index(ax, dx):
 255   return t_dist_table[dx][ax]
 256
 257
 258 def t_dist_index_of_degree(degree):
 259   limit = len(t_dist_table) - 1
 260   dx = 0
 261   while dx < limit and t_dist_degree_at_index(dx+1) <= degree:
 262     dx += 1
 263   return dx
 264
 265
 266 def t_dist_index_of_alpha(alpha):
 267   limit = len(t_dist_table[0]) - 1
 268   ax = 0
 269   while ax < limit and t_dist_alpha_at_index(ax+1) >= alpha:
 270     ax += 1
 271   return ax
 272
 273
 274 def t_dist_index_of_value(dx, value):
 275   limit = len(t_dist_table[dx]) - 1
 276   ax = 0
 277   while ax < limit and t_dist_value_at_index(ax+1, dx) < value:
 278     ax += 1
 279   return ax
 280
 281
 282 def t_dist_value_within_deviations(dx, ax, deviations):
 283   degree = t_dist_degree_at_index(dx)
 284   count = degree + 1
 285   root = math.sqrt(count)
 286   value = t_dist_value_at_index(ax, dx)
 287   nominal = value / root
 288   comparison = nominal <= deviations
 289   return comparison
 290
 291
 292 def t_dist_index_of_degree_for_deviations(ax, deviations):
 293   limit = len(t_dist_table) - 1
 294   dx = 1
 295   while dx < limit and not t_dist_value_within_deviations(dx, ax, deviations):
 296     dx += 1
 297   return dx
 298
 299
 300 def find_t_dist_value(alpha, degree):
 301   """ Return the t-distribution value.
 302   The parameters are alpha and degree of freedom.
 303   """
 304   dx = t_dist_index_of_degree(degree)
 305   ax = t_dist_index_of_alpha(alpha)
 306   return t_dist_value_at_index(ax, dx)
 307
 308
 309 def find_t_dist_alpha(value, degree):
 310   """ Return the alpha.
 311   The parameters are the t-distribution value for a given degree of freedom.
 312   """
 313   dx = t_dist_index_of_degree(degree)
 314   ax = t_dist_index_of_value(dx, value)
 315   return t_dist_alpha_at_index(ax)
 316
 317
 318 def find_t_dist_degree(alpha, deviations):
 319   """ Return the degree-of-freedom.
 320   The parameters are the desired alpha and the number of standard deviations
 321   away from the mean that the degree should handle.
 322   """
 323   ax = t_dist_index_of_alpha(alpha)
 324   dx = t_dist_index_of_degree_for_deviations(ax, deviations)
 325   return t_dist_degree_at_index(dx)
 326
 327
 328 ############################################################## Core Statistical
 329
 330
 331 # This section provides the core statistical classes and functions.
 332
 333
 334 class Accumulator:
 335
 336   """ An accumulator for statistical information using arithmetic mean.  """
 337
 338   def __init__(self):
 339     self.count = 0
 340     self.mean = 0
 341     self.sumsqdiff = 0
 342
 343   def insert(self, value):
 344     self.count += 1
 345     diff = value - self.mean
 346     self.mean += diff / self.count
 347     self.sumsqdiff += (self.count - 1) * diff * diff / self.count
 348
 349
 350 def fill_accumulator_from_values(values):
 351   accumulator = Accumulator()
 352   for value in values:
 353     accumulator.insert(value)
 354   return accumulator
 355
 356
 357 def alpha_from_confidence(confidence):
 358   scrubbed = min(99.99, max(confidence, 60))
 359   return (100.0 - scrubbed) / 200.0
 360
 361
 362 def confidence_from_alpha(alpha):
 363   return 100 - 200 * alpha
 364
 365
 366 class Sample:
 367
 368   """ A description of a sample using an arithmetic mean.  """
 369
 370   def __init__(self, accumulator, alpha):
 371     if accumulator.count < 3:
 372       sys.exit("Samples must contain three trials.")
 373     self.count = accumulator.count
 374     self.mean = accumulator.mean
 375     variance = accumulator.sumsqdiff / (self.count - 1)
 376     self.deviation = math.sqrt(variance)
 377     self.error = self.deviation / math.sqrt(self.count)
 378     self.alpha = alpha
 379     self.radius = find_t_dist_value(alpha, self.count - 1) * self.error
 380
 381   def alpha_for_radius(self, radius):
 382     return find_t_dist_alpha(divide(radius, self.error), self.count)
 383
 384   def degree_for_radius(self, radius):
 385     return find_t_dist_degree(self.alpha, divide(radius, self.deviation))
 386
 387   def __str__(self):
 388     text = "trial count is " + text_number(self.count)
 389     text += ", mean is " + text_number(self.mean)
 390     text += " (" + text_number(confidence_from_alpha(self.alpha)) +"%"
 391     text += " confidence in " + text_number(self.mean - self.radius)
 392     text += " to " + text_number(self.mean + self.radius) + ")"
 393     text += ",\nstd.deviation is " + text_number(self.deviation)
 394     text += ", std.error is " + text_number(self.error)
 395     return text
 396
 397
 398 def sample_from_values(values, alpha):
 399   accumulator = fill_accumulator_from_values(values)
 400   return Sample(accumulator, alpha)
 401
 402
 403 class Comparison:
 404
 405   """ A comparison of two samples using arithmetic means.  """
 406
 407   def __init__(self, first, second, alpha):
 408     if first.mean > second.mean:
 409       self.upper = first
 410       self.lower = second
 411       self.larger = "first"
 412     else:
 413       self.upper = second
 414       self.lower = first
 415       self.larger = "second"
 416     self.a_wanted = alpha
 417     radius = self.upper.mean - self.lower.mean
 418     rising = self.lower.alpha_for_radius(radius)
 419     falling = self.upper.alpha_for_radius(radius)
 420     self.a_actual = max(rising, falling)
 421     rising = self.lower.degree_for_radius(radius)
 422     falling = self.upper.degree_for_radius(radius)
 423     self.count = max(rising, falling) + 1
 424
 425   def __str__(self):
 426     message = "The " + self.larger + " sample appears to be "
 427     change = divide(self.upper.mean, self.lower.mean) - 1
 428     message += text_percent(change) + " larger,\n"
 429     confidence = confidence_from_alpha(self.a_actual)
 430     if confidence >= 60:
 431       message += "with " + text_number(confidence) + "% confidence"
 432       message += " of being larger."
 433     else:
 434       message += "but with no confidence of actually being larger."
 435     if self.a_actual > self.a_wanted:
 436       confidence = confidence_from_alpha(self.a_wanted)
 437       message += "\nTo reach " + text_number(confidence) + "% confidence,"
 438       if self.count < 100:
 439         message += " you need roughly " + text_number(self.count) + " trials,\n"
 440         message += "assuming the standard deviation is stable, which is iffy."
 441       else:
 442         message += "\nyou need to reduce the larger deviation"
 443         message += " or increase the number of trials."
 444     return message
 445
 446
 447 ############################################################ Single Value Files
 448
 449
 450 # This section provides functions to compare two raw data files,
 451 # each containing a whole sample consisting of single number per line.
 452
 453
 454 # Should you repurpose this script, this code might help.
 455 #
 456 #def values_from_data_file(filename):
 457 #  for line in lines_in_file(filename):
 458 #    yield float(line)
 459
 460
 461 # Should you repurpose this script, this code might help.
 462 #
 463 #def sample_from_data_file(filename, alpha):
 464 #  confidence = confidence_from_alpha(alpha)
 465 #  text = "\nArithmetic sample for data file\n\"" + filename + "\""
 466 #  text += " with desired confidence " + text_number(confidence) + " is "
 467 #  print text
 468 #  values = values_from_data_file(filename)
 469 #  sample = sample_from_values(values, alpha)
 470 #  print sample
 471 #  return sample
 472
 473
 474 # Should you repurpose this script, this code might help.
 475 #
 476 #def compare_two_data_files(filename1, filename2, confidence):
 477 #  alpha = alpha_from_confidence(confidence)
 478 #  sample1 = sample_from_data_file(filename1, alpha)
 479 #  sample2 = sample_from_data_file(filename2, alpha)
 480 #  print
 481 #  print Comparison(sample1, sample2, alpha)
 482
 483
 484 # Should you repurpose this script, this code might help.
 485 #
 486 #def command_two_data_files():
 487 #  argc = len(sys.argv)
 488 #  if argc < 2 or 4 < argc:
 489 #    message = "usage: " + sys.argv[0]
 490 #    message += " file-name file-name [confidence]"
 491 #    print message
 492 #  else:
 493 #    filename1 = sys.argv[1]
 494 #    filename2 = sys.argv[2]
 495 #    if len(sys.argv) >= 4:
 496 #      confidence = int(sys.argv[3])
 497 #    else:
 498 #      confidence = 95
 499 #  compare_two_data_files(filename1, filename2, confidence)
 500
 501
 502 ############################################### -ftime-report TimeVar Log Files
 503
 504
 505 # This section provides functions to compare two sets of -ftime-report log
 506 # files.  Each set is a sample, where each data point is derived from the
 507 # sum of values in a single log file.
 508
 509
 510 label = r"^ *([^:]*[^: ]) *:"
 511 number = r" *([0-9.]*) *"
 512 percent = r"\( *[0-9]*\%\)"
 513 numpct = number + percent
 514 total_format = label + number + number + number + number + " kB\n"
 515 total_parser = re.compile(total_format)
 516 tmvar_format = label + numpct + " usr" + numpct + " sys"
 517 tmvar_format += numpct + " wall" + number + " kB " + percent + " ggc\n"
 518 tmvar_parser = re.compile(tmvar_format)
 519 replace = r"\2\t\3\t\4\t\5\t\1"
 520
 521
 522 def split_time_report(lines, pattern):
 523   if pattern == "TOTAL":
 524     parser = total_parser
 525   else:
 526     parser = tmvar_parser
 527   for line in lines:
 528     modified = parser.sub(replace, line)
 529     if modified != line:
 530       yield re.split("\t", modified)
 531
 532
 533 def extract_cpu_time(tvtuples):
 534   for tuple in tvtuples:
 535     yield float(tuple[0]) + float(tuple[1])
 536
 537
 538 def sum_values(values):
 539   sum = 0
 540   for value in values:
 541     sum += value
 542   return sum
 543
 544
 545 def extract_time_for_timevar_log(filename, pattern):
 546   lines = lines_in_file(filename)
 547   tmvars = lines_containing_pattern(pattern, lines)
 548   tuples = split_time_report(tmvars, pattern)
 549   times = extract_cpu_time(tuples)
 550   return sum_values(times)
 551
 552
 553 def extract_times_for_timevar_logs(filelist, pattern):
 554   for filename in filelist:
 555     yield extract_time_for_timevar_log(filename, pattern)
 556
 557
 558 def sample_from_timevar_logs(fileglob, pattern, alpha):
 559   confidence = confidence_from_alpha(alpha)
 560   text = "\nArithmetic sample for timevar log files\n\"" + fileglob + "\""
 561   text += "\nand selecting lines containing \"" + pattern + "\""
 562   text += " with desired confidence " + text_number(confidence) + " is "
 563   print text
 564   filelist = match_files(fileglob)
 565   values = extract_times_for_timevar_logs(filelist, pattern)
 566   sample = sample_from_values(values, alpha)
 567   print sample
 568   return sample
 569
 570
 571 def compare_two_timevar_logs(fileglob1, fileglob2, pattern, confidence):
 572   alpha = alpha_from_confidence(confidence)
 573   sample1 = sample_from_timevar_logs(fileglob1, pattern, alpha)
 574   sample2 = sample_from_timevar_logs(fileglob2, pattern, alpha)
 575   print
 576   print Comparison(sample1, sample2, alpha)
 577
 578
 579 def command_two_timevar_logs():
 580   argc = len(sys.argv)
 581   if argc < 3 or 5 < argc:
 582     message = "usage: " + sys.argv[0]
 583     message += " file-pattern file-pattern [line-pattern [confidence]]"
 584     print message
 585   else:
 586     filepat1 = sys.argv[1]
 587     filepat2 = sys.argv[2]
 588     if len(sys.argv) >= 5:
 589       confidence = int(sys.argv[4])
 590     else:
 591       confidence = 95
 592     if len(sys.argv) >= 4:
 593       linepat = sys.argv[3]
 594     else:
 595       linepat = "TOTAL"
 596     compare_two_timevar_logs(filepat1, filepat2, linepat, confidence)
 597
 598
 599 ########################################################################## Main
 600
 601
 602 # This section is the main code, implementing the command.
 603
 604
 605 command_two_timevar_logs()