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 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 30The intent of this script is to compare compile-time performance of two 31different versions of the compiler. Each version of the compiler must be 32run at least three times with the -ftime-report option. Each log file 33represents a data point, or trial. The set of trials for each compiler 34version constitutes a sample. The ouput of the script is a description 35of the statistically significant difference between the two version of 36the compiler. 37 38The 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 65The most common use of the script is total compile-time comparison between 66logfiles stored in different directories. 67 68compare_two_ftime_report_sets "Log1/*perf" "Log2/*perf" 69 70One can also look at parsing time, but expecting a lower confidence. 71 72compare_two_ftime_report_sets "Log1/*perf" "Log2/*perf" "^phase parsing" 75 73 74""" 75 76 77import os 78import sys 79import fnmatch 80import glob 81import re 82import math 83 84 85####################################################################### Utility 86 87 88def 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 112def 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 119def 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 127def 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 140def strip_redundant_digits(numrep): 141 if numrep.find(".") == -1: 142 return numrep 143 return numrep.rstrip("0").rstrip(".") 144 145 146def text_number(number): 147 return strip_redundant_digits("%g" % number) 148 149 150def 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 159def text_significant(digits, number): 160 return text_number(round_significant(digits, number)) 161 162 163def 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 181t_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 243def 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 250def t_dist_degree_at_index(dx): 251 return t_dist_table[dx][0] 252 253 254def t_dist_value_at_index(ax, dx): 255 return t_dist_table[dx][ax] 256 257 258def 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 266def 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 274def 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 282def 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 292def 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 300def 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 309def 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 318def 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 334class 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 350def fill_accumulator_from_values(values): 351 accumulator = Accumulator() 352 for value in values: 353 accumulator.insert(value) 354 return accumulator 355 356 357def alpha_from_confidence(confidence): 358 scrubbed = min(99.99, max(confidence, 60)) 359 return (100.0 - scrubbed) / 200.0 360 361 362def confidence_from_alpha(alpha): 363 return 100 - 200 * alpha 364 365 366class 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 398def sample_from_values(values, alpha): 399 accumulator = fill_accumulator_from_values(values) 400 return Sample(accumulator, alpha) 401 402 403class 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 510label = r"^ *([^:]*[^: ]) *:" 511number = r" *([0-9.]*) *" 512percent = r"\( *[0-9]*\%\)" 513numpct = number + percent 514total_format = label + number + number + number + number + " kB\n" 515total_parser = re.compile(total_format) 516tmvar_format = label + numpct + " usr" + numpct + " sys" 517tmvar_format += numpct + " wall" + number + " kB " + percent + " ggc\n" 518tmvar_parser = re.compile(tmvar_format) 519replace = r"\2\t\3\t\4\t\5\t\1" 520 521 522def 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 533def extract_cpu_time(tvtuples): 534 for tuple in tvtuples: 535 yield float(tuple[0]) + float(tuple[1]) 536 537 538def sum_values(values): 539 sum = 0 540 for value in values: 541 sum += value 542 return sum 543 544 545def 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 553def extract_times_for_timevar_logs(filelist, pattern): 554 for filename in filelist: 555 yield extract_time_for_timevar_log(filename, pattern) 556 557 558def 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 571def 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 579def 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 605command_two_timevar_logs() 606