1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/ipc/chromium/src/base/histogram.cc Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,1286 @@
1.4 +// Copyright (c) 2011 The Chromium Authors. All rights reserved.
1.5 +// Use of this source code is governed by a BSD-style license that can be
1.6 +// found in the LICENSE file.
1.7 +
1.8 +// Histogram is an object that aggregates statistics, and can summarize them in
1.9 +// various forms, including ASCII graphical, HTML, and numerically (as a
1.10 +// vector of numbers corresponding to each of the aggregating buckets).
1.11 +// See header file for details and examples.
1.12 +
1.13 +#include "base/histogram.h"
1.14 +
1.15 +#include <math.h>
1.16 +
1.17 +#include <algorithm>
1.18 +#include <string>
1.19 +
1.20 +#include "base/logging.h"
1.21 +#include "base/pickle.h"
1.22 +#include "base/string_util.h"
1.23 +#include "base/logging.h"
1.24 +
1.25 +namespace base {
1.26 +
1.27 +#define DVLOG(x) CHROMIUM_LOG(ERROR)
1.28 +#define CHECK_GT DCHECK_GT
1.29 +#define CHECK_LT DCHECK_LT
1.30 +typedef ::Lock Lock;
1.31 +typedef ::AutoLock AutoLock;
1.32 +
1.33 +// Static table of checksums for all possible 8 bit bytes.
1.34 +const uint32_t Histogram::kCrcTable[256] = {0x0, 0x77073096L, 0xee0e612cL,
1.35 +0x990951baL, 0x76dc419L, 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0xedb8832L,
1.36 +0x79dcb8a4L, 0xe0d5e91eL, 0x97d2d988L, 0x9b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
1.37 +0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL, 0x1adad47dL,
1.38 +0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L, 0x646ba8c0L, 0xfd62f97aL,
1.39 +0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L, 0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L,
1.40 +0x4c69105eL, 0xd56041e4L, 0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL,
1.41 +0xa50ab56bL, 0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
1.42 +0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL, 0xc8d75180L,
1.43 +0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L, 0xb8bda50fL, 0x2802b89eL,
1.44 +0x5f058808L, 0xc60cd9b2L, 0xb10be924L, 0x2f6f7c87L, 0x58684c11L, 0xc1611dabL,
1.45 +0xb6662d3dL, 0x76dc4190L, 0x1db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L,
1.46 +0x6b6b51fL, 0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0xf00f934L, 0x9609a88eL,
1.47 +0xe10e9818L, 0x7f6a0dbbL, 0x86d3d2dL, 0x91646c97L, 0xe6635c01L, 0x6b6b51f4L,
1.48 +0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL, 0x1b01a57bL, 0x8208f4c1L,
1.49 +0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L, 0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL,
1.50 +0x15da2d49L, 0x8cd37cf3L, 0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L,
1.51 +0xd4bb30e2L, 0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
1.52 +0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L, 0xaa0a4c5fL,
1.53 +0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L, 0xc90c2086L, 0x5768b525L,
1.54 +0x206f85b3L, 0xb966d409L, 0xce61e49fL, 0x5edef90eL, 0x29d9c998L, 0xb0d09822L,
1.55 +0xc7d7a8b4L, 0x59b33d17L, 0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L,
1.56 +0x9abfb3b6L, 0x3b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x4db2615L,
1.57 +0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0xd6d6a3eL, 0x7a6a5aa8L, 0xe40ecf0bL,
1.58 +0x9309ff9dL, 0xa00ae27L, 0x7d079eb1L, 0xf00f9344L, 0x8708a3d2L, 0x1e01f268L,
1.59 +0x6906c2feL, 0xf762575dL, 0x806567cbL, 0x196c3671L, 0x6e6b06e7L, 0xfed41b76L,
1.60 +0x89d32be0L, 0x10da7a5aL, 0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L,
1.61 +0x60b08ed5L, 0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
1.62 +0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL, 0x36034af6L,
1.63 +0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL, 0x4669be79L, 0xcb61b38cL,
1.64 +0xbc66831aL, 0x256fd2a0L, 0x5268e236L, 0xcc0c7795L, 0xbb0b4703L, 0x220216b9L,
1.65 +0x5505262fL, 0xc5ba3bbeL, 0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L,
1.66 +0xb5d0cf31L, 0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
1.67 +0x26d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x5005713L, 0x95bf4a82L,
1.68 +0xe2b87a14L, 0x7bb12baeL, 0xcb61b38L, 0x92d28e9bL, 0xe5d5be0dL, 0x7cdcefb7L,
1.69 +0xbdbdf21L, 0x86d3d2d4L, 0xf1d4e242L, 0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL,
1.70 +0xf6b9265bL, 0x6fb077e1L, 0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL,
1.71 +0x11010b5cL, 0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
1.72 +0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L, 0x4969474dL,
1.73 +0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L, 0x37d83bf0L, 0xa9bcae53L,
1.74 +0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L, 0xbdbdf21cL, 0xcabac28aL, 0x53b39330L,
1.75 +0x24b4a3a6L, 0xbad03605L, 0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL,
1.76 +0xc4614ab8L, 0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
1.77 +0x2d02ef8dL,
1.78 +};
1.79 +
1.80 +typedef Histogram::Count Count;
1.81 +
1.82 +// static
1.83 +const size_t Histogram::kBucketCount_MAX = 16384u;
1.84 +
1.85 +Histogram* Histogram::FactoryGet(const std::string& name,
1.86 + Sample minimum,
1.87 + Sample maximum,
1.88 + size_t bucket_count,
1.89 + Flags flags) {
1.90 + Histogram* histogram(NULL);
1.91 +
1.92 + // Defensive code.
1.93 + if (minimum < 1)
1.94 + minimum = 1;
1.95 + if (maximum > kSampleType_MAX - 1)
1.96 + maximum = kSampleType_MAX - 1;
1.97 +
1.98 + if (!StatisticsRecorder::FindHistogram(name, &histogram)) {
1.99 + // Extra variable is not needed... but this keeps this section basically
1.100 + // identical to other derived classes in this file (and compiler will
1.101 + // optimize away the extra variable.
1.102 + Histogram* tentative_histogram =
1.103 + new Histogram(name, minimum, maximum, bucket_count);
1.104 + tentative_histogram->InitializeBucketRange();
1.105 + tentative_histogram->SetFlags(flags);
1.106 + histogram =
1.107 + StatisticsRecorder::RegisterOrDeleteDuplicate(tentative_histogram);
1.108 + }
1.109 +
1.110 + DCHECK_EQ(HISTOGRAM, histogram->histogram_type());
1.111 + DCHECK(histogram->HasConstructorArguments(minimum, maximum, bucket_count));
1.112 + return histogram;
1.113 +}
1.114 +
1.115 +Histogram* Histogram::FactoryTimeGet(const std::string& name,
1.116 + TimeDelta minimum,
1.117 + TimeDelta maximum,
1.118 + size_t bucket_count,
1.119 + Flags flags) {
1.120 + return FactoryGet(name, minimum.InMilliseconds(), maximum.InMilliseconds(),
1.121 + bucket_count, flags);
1.122 +}
1.123 +
1.124 +void Histogram::Add(int value) {
1.125 + if (value > kSampleType_MAX - 1)
1.126 + value = kSampleType_MAX - 1;
1.127 + if (value < 0)
1.128 + value = 0;
1.129 + size_t index = BucketIndex(value);
1.130 + DCHECK_GE(value, ranges(index));
1.131 + DCHECK_LT(value, ranges(index + 1));
1.132 + Accumulate(value, 1, index);
1.133 +}
1.134 +
1.135 +void Histogram::Subtract(int value) {
1.136 + if (value > kSampleType_MAX - 1)
1.137 + value = kSampleType_MAX - 1;
1.138 + if (value < 0)
1.139 + value = 0;
1.140 + size_t index = BucketIndex(value);
1.141 + DCHECK_GE(value, ranges(index));
1.142 + DCHECK_LT(value, ranges(index + 1));
1.143 + Accumulate(value, -1, index);
1.144 +}
1.145 +
1.146 +void Histogram::AddBoolean(bool value) {
1.147 + DCHECK(false);
1.148 +}
1.149 +
1.150 +void Histogram::AddSampleSet(const SampleSet& sample) {
1.151 + sample_.Add(sample);
1.152 +}
1.153 +
1.154 +void Histogram::Clear() {
1.155 + SampleSet ss;
1.156 + ss.Resize(*this);
1.157 + sample_ = ss;
1.158 +}
1.159 +
1.160 +void Histogram::SetRangeDescriptions(const DescriptionPair descriptions[]) {
1.161 + DCHECK(false);
1.162 +}
1.163 +
1.164 +// The following methods provide a graphical histogram display.
1.165 +void Histogram::WriteHTMLGraph(std::string* output) const {
1.166 + // TBD(jar) Write a nice HTML bar chart, with divs an mouse-overs etc.
1.167 + output->append("<PRE>");
1.168 + WriteAscii(true, "<br>", output);
1.169 + output->append("</PRE>");
1.170 +}
1.171 +
1.172 +void Histogram::WriteAscii(bool graph_it, const std::string& newline,
1.173 + std::string* output) const {
1.174 + // Get local (stack) copies of all effectively volatile class data so that we
1.175 + // are consistent across our output activities.
1.176 + SampleSet snapshot;
1.177 + SnapshotSample(&snapshot);
1.178 + Count sample_count = snapshot.TotalCount();
1.179 +
1.180 + WriteAsciiHeader(snapshot, sample_count, output);
1.181 + output->append(newline);
1.182 +
1.183 + // Prepare to normalize graphical rendering of bucket contents.
1.184 + double max_size = 0;
1.185 + if (graph_it)
1.186 + max_size = GetPeakBucketSize(snapshot);
1.187 +
1.188 + // Calculate space needed to print bucket range numbers. Leave room to print
1.189 + // nearly the largest bucket range without sliding over the histogram.
1.190 + size_t largest_non_empty_bucket = bucket_count() - 1;
1.191 + while (0 == snapshot.counts(largest_non_empty_bucket)) {
1.192 + if (0 == largest_non_empty_bucket)
1.193 + break; // All buckets are empty.
1.194 + --largest_non_empty_bucket;
1.195 + }
1.196 +
1.197 + // Calculate largest print width needed for any of our bucket range displays.
1.198 + size_t print_width = 1;
1.199 + for (size_t i = 0; i < bucket_count(); ++i) {
1.200 + if (snapshot.counts(i)) {
1.201 + size_t width = GetAsciiBucketRange(i).size() + 1;
1.202 + if (width > print_width)
1.203 + print_width = width;
1.204 + }
1.205 + }
1.206 +
1.207 + int64_t remaining = sample_count;
1.208 + int64_t past = 0;
1.209 + // Output the actual histogram graph.
1.210 + for (size_t i = 0; i < bucket_count(); ++i) {
1.211 + Count current = snapshot.counts(i);
1.212 + if (!current && !PrintEmptyBucket(i))
1.213 + continue;
1.214 + remaining -= current;
1.215 + std::string range = GetAsciiBucketRange(i);
1.216 + output->append(range);
1.217 + for (size_t j = 0; range.size() + j < print_width + 1; ++j)
1.218 + output->push_back(' ');
1.219 + if (0 == current && i < bucket_count() - 1 && 0 == snapshot.counts(i + 1)) {
1.220 + while (i < bucket_count() - 1 && 0 == snapshot.counts(i + 1))
1.221 + ++i;
1.222 + output->append("... ");
1.223 + output->append(newline);
1.224 + continue; // No reason to plot emptiness.
1.225 + }
1.226 + double current_size = GetBucketSize(current, i);
1.227 + if (graph_it)
1.228 + WriteAsciiBucketGraph(current_size, max_size, output);
1.229 + WriteAsciiBucketContext(past, current, remaining, i, output);
1.230 + output->append(newline);
1.231 + past += current;
1.232 + }
1.233 + DCHECK_EQ(sample_count, past);
1.234 +}
1.235 +
1.236 +// static
1.237 +std::string Histogram::SerializeHistogramInfo(const Histogram& histogram,
1.238 + const SampleSet& snapshot) {
1.239 + DCHECK_NE(NOT_VALID_IN_RENDERER, histogram.histogram_type());
1.240 +
1.241 + Pickle pickle;
1.242 + pickle.WriteString(histogram.histogram_name());
1.243 + pickle.WriteInt(histogram.declared_min());
1.244 + pickle.WriteInt(histogram.declared_max());
1.245 + pickle.WriteSize(histogram.bucket_count());
1.246 + pickle.WriteUInt32(histogram.range_checksum());
1.247 + pickle.WriteInt(histogram.histogram_type());
1.248 + pickle.WriteInt(histogram.flags());
1.249 +
1.250 + snapshot.Serialize(&pickle);
1.251 + return std::string(static_cast<const char*>(pickle.data()), pickle.size());
1.252 +}
1.253 +
1.254 +// static
1.255 +bool Histogram::DeserializeHistogramInfo(const std::string& histogram_info) {
1.256 + if (histogram_info.empty()) {
1.257 + return false;
1.258 + }
1.259 +
1.260 + Pickle pickle(histogram_info.data(),
1.261 + static_cast<int>(histogram_info.size()));
1.262 + std::string histogram_name;
1.263 + int declared_min;
1.264 + int declared_max;
1.265 + size_t bucket_count;
1.266 + uint32_t range_checksum;
1.267 + int histogram_type;
1.268 + int pickle_flags;
1.269 + SampleSet sample;
1.270 +
1.271 + void* iter = NULL;
1.272 + if (!pickle.ReadString(&iter, &histogram_name) ||
1.273 + !pickle.ReadInt(&iter, &declared_min) ||
1.274 + !pickle.ReadInt(&iter, &declared_max) ||
1.275 + !pickle.ReadSize(&iter, &bucket_count) ||
1.276 + !pickle.ReadUInt32(&iter, &range_checksum) ||
1.277 + !pickle.ReadInt(&iter, &histogram_type) ||
1.278 + !pickle.ReadInt(&iter, &pickle_flags) ||
1.279 + !sample.Histogram::SampleSet::Deserialize(&iter, pickle)) {
1.280 + CHROMIUM_LOG(ERROR) << "Pickle error decoding Histogram: " << histogram_name;
1.281 + return false;
1.282 + }
1.283 + DCHECK(pickle_flags & kIPCSerializationSourceFlag);
1.284 + // Since these fields may have come from an untrusted renderer, do additional
1.285 + // checks above and beyond those in Histogram::Initialize()
1.286 + if (declared_max <= 0 || declared_min <= 0 || declared_max < declared_min ||
1.287 + INT_MAX / sizeof(Count) <= bucket_count || bucket_count < 2) {
1.288 + CHROMIUM_LOG(ERROR) << "Values error decoding Histogram: " << histogram_name;
1.289 + return false;
1.290 + }
1.291 +
1.292 + Flags flags = static_cast<Flags>(pickle_flags & ~kIPCSerializationSourceFlag);
1.293 +
1.294 + DCHECK_NE(NOT_VALID_IN_RENDERER, histogram_type);
1.295 +
1.296 + Histogram* render_histogram(NULL);
1.297 +
1.298 + if (histogram_type == HISTOGRAM) {
1.299 + render_histogram = Histogram::FactoryGet(
1.300 + histogram_name, declared_min, declared_max, bucket_count, flags);
1.301 + } else if (histogram_type == LINEAR_HISTOGRAM) {
1.302 + render_histogram = LinearHistogram::FactoryGet(
1.303 + histogram_name, declared_min, declared_max, bucket_count, flags);
1.304 + } else if (histogram_type == BOOLEAN_HISTOGRAM) {
1.305 + render_histogram = BooleanHistogram::FactoryGet(histogram_name, flags);
1.306 + } else {
1.307 + CHROMIUM_LOG(ERROR) << "Error Deserializing Histogram Unknown histogram_type: "
1.308 + << histogram_type;
1.309 + return false;
1.310 + }
1.311 +
1.312 + DCHECK_EQ(render_histogram->declared_min(), declared_min);
1.313 + DCHECK_EQ(render_histogram->declared_max(), declared_max);
1.314 + DCHECK_EQ(render_histogram->bucket_count(), bucket_count);
1.315 + DCHECK_EQ(render_histogram->range_checksum(), range_checksum);
1.316 + DCHECK_EQ(render_histogram->histogram_type(), histogram_type);
1.317 +
1.318 + if (render_histogram->flags() & kIPCSerializationSourceFlag) {
1.319 + DVLOG(1) << "Single process mode, histogram observed and not copied: "
1.320 + << histogram_name;
1.321 + } else {
1.322 + DCHECK_EQ(flags & render_histogram->flags(), flags);
1.323 + render_histogram->AddSampleSet(sample);
1.324 + }
1.325 +
1.326 + return true;
1.327 +}
1.328 +
1.329 +//------------------------------------------------------------------------------
1.330 +// Methods for the validating a sample and a related histogram.
1.331 +//------------------------------------------------------------------------------
1.332 +
1.333 +Histogram::Inconsistencies Histogram::FindCorruption(
1.334 + const SampleSet& snapshot) const {
1.335 + int inconsistencies = NO_INCONSISTENCIES;
1.336 + Sample previous_range = -1; // Bottom range is always 0.
1.337 + int64_t count = 0;
1.338 + for (size_t index = 0; index < bucket_count(); ++index) {
1.339 + count += snapshot.counts(index);
1.340 + int new_range = ranges(index);
1.341 + if (previous_range >= new_range)
1.342 + inconsistencies |= BUCKET_ORDER_ERROR;
1.343 + previous_range = new_range;
1.344 + }
1.345 +
1.346 + if (!HasValidRangeChecksum())
1.347 + inconsistencies |= RANGE_CHECKSUM_ERROR;
1.348 +
1.349 + int64_t delta64 = snapshot.redundant_count() - count;
1.350 + if (delta64 != 0) {
1.351 + int delta = static_cast<int>(delta64);
1.352 + if (delta != delta64)
1.353 + delta = INT_MAX; // Flag all giant errors as INT_MAX.
1.354 + // Since snapshots of histograms are taken asynchronously relative to
1.355 + // sampling (and snapped from different threads), it is pretty likely that
1.356 + // we'll catch a redundant count that doesn't match the sample count. We
1.357 + // allow for a certain amount of slop before flagging this as an
1.358 + // inconsistency. Even with an inconsistency, we'll snapshot it again (for
1.359 + // UMA in about a half hour, so we'll eventually get the data, if it was
1.360 + // not the result of a corruption. If histograms show that 1 is "too tight"
1.361 + // then we may try to use 2 or 3 for this slop value.
1.362 + const int kCommonRaceBasedCountMismatch = 1;
1.363 + if (delta > 0) {
1.364 + UMA_HISTOGRAM_COUNTS("Histogram.InconsistentCountHigh", delta);
1.365 + if (delta > kCommonRaceBasedCountMismatch)
1.366 + inconsistencies |= COUNT_HIGH_ERROR;
1.367 + } else {
1.368 + DCHECK_GT(0, delta);
1.369 + UMA_HISTOGRAM_COUNTS("Histogram.InconsistentCountLow", -delta);
1.370 + if (-delta > kCommonRaceBasedCountMismatch)
1.371 + inconsistencies |= COUNT_LOW_ERROR;
1.372 + }
1.373 + }
1.374 + return static_cast<Inconsistencies>(inconsistencies);
1.375 +}
1.376 +
1.377 +Histogram::ClassType Histogram::histogram_type() const {
1.378 + return HISTOGRAM;
1.379 +}
1.380 +
1.381 +Histogram::Sample Histogram::ranges(size_t i) const {
1.382 + return ranges_[i];
1.383 +}
1.384 +
1.385 +size_t Histogram::bucket_count() const {
1.386 + return bucket_count_;
1.387 +}
1.388 +
1.389 +// Do a safe atomic snapshot of sample data.
1.390 +// This implementation assumes we are on a safe single thread.
1.391 +void Histogram::SnapshotSample(SampleSet* sample) const {
1.392 + // Note locking not done in this version!!!
1.393 + *sample = sample_;
1.394 +}
1.395 +
1.396 +bool Histogram::HasConstructorArguments(Sample minimum,
1.397 + Sample maximum,
1.398 + size_t bucket_count) {
1.399 + return ((minimum == declared_min_) && (maximum == declared_max_) &&
1.400 + (bucket_count == bucket_count_));
1.401 +}
1.402 +
1.403 +bool Histogram::HasConstructorTimeDeltaArguments(TimeDelta minimum,
1.404 + TimeDelta maximum,
1.405 + size_t bucket_count) {
1.406 + return ((minimum.InMilliseconds() == declared_min_) &&
1.407 + (maximum.InMilliseconds() == declared_max_) &&
1.408 + (bucket_count == bucket_count_));
1.409 +}
1.410 +
1.411 +bool Histogram::HasValidRangeChecksum() const {
1.412 + return CalculateRangeChecksum() == range_checksum_;
1.413 +}
1.414 +
1.415 +size_t Histogram::SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf)
1.416 +{
1.417 + size_t n = 0;
1.418 + n += aMallocSizeOf(this);
1.419 + // We're not allowed to do deep dives into STL data structures. This
1.420 + // is as close as we can get to measuring this array.
1.421 + n += aMallocSizeOf(&ranges_[0]);
1.422 + n += sample_.SizeOfExcludingThis(aMallocSizeOf);
1.423 + return n;
1.424 +}
1.425 +
1.426 +size_t Histogram::SampleSet::SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf)
1.427 +{
1.428 + // We're not allowed to do deep dives into STL data structures. This
1.429 + // is as close as we can get to measuring this array.
1.430 + return aMallocSizeOf(&counts_[0]);
1.431 +}
1.432 +
1.433 +Histogram::Histogram(const std::string& name, Sample minimum,
1.434 + Sample maximum, size_t bucket_count)
1.435 + : sample_(),
1.436 + histogram_name_(name),
1.437 + declared_min_(minimum),
1.438 + declared_max_(maximum),
1.439 + bucket_count_(bucket_count),
1.440 + flags_(kNoFlags),
1.441 + ranges_(bucket_count + 1, 0),
1.442 + range_checksum_(0) {
1.443 + Initialize();
1.444 +}
1.445 +
1.446 +Histogram::Histogram(const std::string& name, TimeDelta minimum,
1.447 + TimeDelta maximum, size_t bucket_count)
1.448 + : sample_(),
1.449 + histogram_name_(name),
1.450 + declared_min_(static_cast<int> (minimum.InMilliseconds())),
1.451 + declared_max_(static_cast<int> (maximum.InMilliseconds())),
1.452 + bucket_count_(bucket_count),
1.453 + flags_(kNoFlags),
1.454 + ranges_(bucket_count + 1, 0),
1.455 + range_checksum_(0) {
1.456 + Initialize();
1.457 +}
1.458 +
1.459 +Histogram::~Histogram() {
1.460 + if (StatisticsRecorder::dump_on_exit()) {
1.461 + std::string output;
1.462 + WriteAscii(true, "\n", &output);
1.463 + CHROMIUM_LOG(INFO) << output;
1.464 + }
1.465 +
1.466 + // Just to make sure most derived class did this properly...
1.467 + DCHECK(ValidateBucketRanges());
1.468 +}
1.469 +
1.470 +// Calculate what range of values are held in each bucket.
1.471 +// We have to be careful that we don't pick a ratio between starting points in
1.472 +// consecutive buckets that is sooo small, that the integer bounds are the same
1.473 +// (effectively making one bucket get no values). We need to avoid:
1.474 +// ranges_[i] == ranges_[i + 1]
1.475 +// To avoid that, we just do a fine-grained bucket width as far as we need to
1.476 +// until we get a ratio that moves us along at least 2 units at a time. From
1.477 +// that bucket onward we do use the exponential growth of buckets.
1.478 +void Histogram::InitializeBucketRange() {
1.479 + double log_max = log(static_cast<double>(declared_max()));
1.480 + double log_ratio;
1.481 + double log_next;
1.482 + size_t bucket_index = 1;
1.483 + Sample current = declared_min();
1.484 + SetBucketRange(bucket_index, current);
1.485 + while (bucket_count() > ++bucket_index) {
1.486 + double log_current;
1.487 + log_current = log(static_cast<double>(current));
1.488 + // Calculate the count'th root of the range.
1.489 + log_ratio = (log_max - log_current) / (bucket_count() - bucket_index);
1.490 + // See where the next bucket would start.
1.491 + log_next = log_current + log_ratio;
1.492 + int next;
1.493 + next = static_cast<int>(floor(exp(log_next) + 0.5));
1.494 + if (next > current)
1.495 + current = next;
1.496 + else
1.497 + ++current; // Just do a narrow bucket, and keep trying.
1.498 + SetBucketRange(bucket_index, current);
1.499 + }
1.500 + ResetRangeChecksum();
1.501 +
1.502 + DCHECK_EQ(bucket_count(), bucket_index);
1.503 +}
1.504 +
1.505 +bool Histogram::PrintEmptyBucket(size_t index) const {
1.506 + return true;
1.507 +}
1.508 +
1.509 +size_t Histogram::BucketIndex(Sample value) const {
1.510 + // Use simple binary search. This is very general, but there are better
1.511 + // approaches if we knew that the buckets were linearly distributed.
1.512 + DCHECK_LE(ranges(0), value);
1.513 + DCHECK_GT(ranges(bucket_count()), value);
1.514 + size_t under = 0;
1.515 + size_t over = bucket_count();
1.516 + size_t mid;
1.517 +
1.518 + do {
1.519 + DCHECK_GE(over, under);
1.520 + mid = under + (over - under)/2;
1.521 + if (mid == under)
1.522 + break;
1.523 + if (ranges(mid) <= value)
1.524 + under = mid;
1.525 + else
1.526 + over = mid;
1.527 + } while (true);
1.528 +
1.529 + DCHECK_LE(ranges(mid), value);
1.530 + CHECK_GT(ranges(mid+1), value);
1.531 + return mid;
1.532 +}
1.533 +
1.534 +// Use the actual bucket widths (like a linear histogram) until the widths get
1.535 +// over some transition value, and then use that transition width. Exponentials
1.536 +// get so big so fast (and we don't expect to see a lot of entries in the large
1.537 +// buckets), so we need this to make it possible to see what is going on and
1.538 +// not have 0-graphical-height buckets.
1.539 +double Histogram::GetBucketSize(Count current, size_t i) const {
1.540 + DCHECK_GT(ranges(i + 1), ranges(i));
1.541 + static const double kTransitionWidth = 5;
1.542 + double denominator = ranges(i + 1) - ranges(i);
1.543 + if (denominator > kTransitionWidth)
1.544 + denominator = kTransitionWidth; // Stop trying to normalize.
1.545 + return current/denominator;
1.546 +}
1.547 +
1.548 +void Histogram::ResetRangeChecksum() {
1.549 + range_checksum_ = CalculateRangeChecksum();
1.550 +}
1.551 +
1.552 +const std::string Histogram::GetAsciiBucketRange(size_t i) const {
1.553 + std::string result;
1.554 + if (kHexRangePrintingFlag & flags_)
1.555 + StringAppendF(&result, "%#x", ranges(i));
1.556 + else
1.557 + StringAppendF(&result, "%d", ranges(i));
1.558 + return result;
1.559 +}
1.560 +
1.561 +// Update histogram data with new sample.
1.562 +void Histogram::Accumulate(Sample value, Count count, size_t index) {
1.563 + // Note locking not done in this version!!!
1.564 + sample_.AccumulateWithExponentialStats(value, count, index,
1.565 + flags_ & kExtendedStatisticsFlag);
1.566 +}
1.567 +
1.568 +void Histogram::SetBucketRange(size_t i, Sample value) {
1.569 + DCHECK_GT(bucket_count_, i);
1.570 + ranges_[i] = value;
1.571 +}
1.572 +
1.573 +bool Histogram::ValidateBucketRanges() const {
1.574 + // Standard assertions that all bucket ranges should satisfy.
1.575 + DCHECK_EQ(bucket_count_ + 1, ranges_.size());
1.576 + DCHECK_EQ(0, ranges_[0]);
1.577 + DCHECK_EQ(declared_min(), ranges_[1]);
1.578 + DCHECK_EQ(declared_max(), ranges_[bucket_count_ - 1]);
1.579 + DCHECK_EQ(kSampleType_MAX, ranges_[bucket_count_]);
1.580 + return true;
1.581 +}
1.582 +
1.583 +uint32_t Histogram::CalculateRangeChecksum() const {
1.584 + DCHECK_EQ(ranges_.size(), bucket_count() + 1);
1.585 + uint32_t checksum = static_cast<uint32_t>(ranges_.size()); // Seed checksum.
1.586 + for (size_t index = 0; index < bucket_count(); ++index)
1.587 + checksum = Crc32(checksum, ranges(index));
1.588 + return checksum;
1.589 +}
1.590 +
1.591 +void Histogram::Initialize() {
1.592 + sample_.Resize(*this);
1.593 + if (declared_min_ < 1)
1.594 + declared_min_ = 1;
1.595 + if (declared_max_ > kSampleType_MAX - 1)
1.596 + declared_max_ = kSampleType_MAX - 1;
1.597 + DCHECK_LE(declared_min_, declared_max_);
1.598 + DCHECK_GT(bucket_count_, 1u);
1.599 + CHECK_LT(bucket_count_, kBucketCount_MAX);
1.600 + size_t maximal_bucket_count = declared_max_ - declared_min_ + 2;
1.601 + DCHECK_LE(bucket_count_, maximal_bucket_count);
1.602 + DCHECK_EQ(0, ranges_[0]);
1.603 + ranges_[bucket_count_] = kSampleType_MAX;
1.604 +}
1.605 +
1.606 +// We generate the CRC-32 using the low order bits to select whether to XOR in
1.607 +// the reversed polynomial 0xedb88320L. This is nice and simple, and allows us
1.608 +// to keep the quotient in a uint32_t. Since we're not concerned about the nature
1.609 +// of corruptions (i.e., we don't care about bit sequencing, since we are
1.610 +// handling memory changes, which are more grotesque) so we don't bother to
1.611 +// get the CRC correct for big-endian vs little-ending calculations. All we
1.612 +// need is a nice hash, that tends to depend on all the bits of the sample, with
1.613 +// very little chance of changes in one place impacting changes in another
1.614 +// place.
1.615 +uint32_t Histogram::Crc32(uint32_t sum, Histogram::Sample range) {
1.616 + const bool kUseRealCrc = true; // TODO(jar): Switch to false and watch stats.
1.617 + if (kUseRealCrc) {
1.618 + union {
1.619 + Histogram::Sample range;
1.620 + unsigned char bytes[sizeof(Histogram::Sample)];
1.621 + } converter;
1.622 + converter.range = range;
1.623 + for (size_t i = 0; i < sizeof(converter); ++i)
1.624 + sum = kCrcTable[(sum & 0xff) ^ converter.bytes[i]] ^ (sum >> 8);
1.625 + } else {
1.626 + // Use hash techniques provided in ReallyFastHash, except we don't care
1.627 + // about "avalanching" (which would worsten the hash, and add collisions),
1.628 + // and we don't care about edge cases since we have an even number of bytes.
1.629 + union {
1.630 + Histogram::Sample range;
1.631 + uint16_t ints[sizeof(Histogram::Sample) / 2];
1.632 + } converter;
1.633 + DCHECK_EQ(sizeof(Histogram::Sample), sizeof(converter));
1.634 + converter.range = range;
1.635 + sum += converter.ints[0];
1.636 + sum = (sum << 16) ^ sum ^ (static_cast<uint32_t>(converter.ints[1]) << 11);
1.637 + sum += sum >> 11;
1.638 + }
1.639 + return sum;
1.640 +}
1.641 +
1.642 +//------------------------------------------------------------------------------
1.643 +// Private methods
1.644 +
1.645 +double Histogram::GetPeakBucketSize(const SampleSet& snapshot) const {
1.646 + double max = 0;
1.647 + for (size_t i = 0; i < bucket_count() ; ++i) {
1.648 + double current_size = GetBucketSize(snapshot.counts(i), i);
1.649 + if (current_size > max)
1.650 + max = current_size;
1.651 + }
1.652 + return max;
1.653 +}
1.654 +
1.655 +void Histogram::WriteAsciiHeader(const SampleSet& snapshot,
1.656 + Count sample_count,
1.657 + std::string* output) const {
1.658 + StringAppendF(output,
1.659 + "Histogram: %s recorded %d samples",
1.660 + histogram_name().c_str(),
1.661 + sample_count);
1.662 + if (0 == sample_count) {
1.663 + DCHECK_EQ(snapshot.sum(), 0);
1.664 + } else {
1.665 + double average = static_cast<float>(snapshot.sum()) / sample_count;
1.666 +
1.667 + StringAppendF(output, ", average = %.1f", average);
1.668 + }
1.669 + if (flags_ & ~kHexRangePrintingFlag)
1.670 + StringAppendF(output, " (flags = 0x%x)", flags_ & ~kHexRangePrintingFlag);
1.671 +}
1.672 +
1.673 +void Histogram::WriteAsciiBucketContext(const int64_t past,
1.674 + const Count current,
1.675 + const int64_t remaining,
1.676 + const size_t i,
1.677 + std::string* output) const {
1.678 + double scaled_sum = (past + current + remaining) / 100.0;
1.679 + WriteAsciiBucketValue(current, scaled_sum, output);
1.680 + if (0 < i) {
1.681 + double percentage = past / scaled_sum;
1.682 + StringAppendF(output, " {%3.1f%%}", percentage);
1.683 + }
1.684 +}
1.685 +
1.686 +void Histogram::WriteAsciiBucketValue(Count current, double scaled_sum,
1.687 + std::string* output) const {
1.688 + StringAppendF(output, " (%d = %3.1f%%)", current, current/scaled_sum);
1.689 +}
1.690 +
1.691 +void Histogram::WriteAsciiBucketGraph(double current_size, double max_size,
1.692 + std::string* output) const {
1.693 + const int k_line_length = 72; // Maximal horizontal width of graph.
1.694 + int x_count = static_cast<int>(k_line_length * (current_size / max_size)
1.695 + + 0.5);
1.696 + int x_remainder = k_line_length - x_count;
1.697 +
1.698 + while (0 < x_count--)
1.699 + output->append("-");
1.700 + output->append("O");
1.701 + while (0 < x_remainder--)
1.702 + output->append(" ");
1.703 +}
1.704 +
1.705 +//------------------------------------------------------------------------------
1.706 +// Methods for the Histogram::SampleSet class
1.707 +//------------------------------------------------------------------------------
1.708 +
1.709 +Histogram::SampleSet::SampleSet()
1.710 + : counts_(),
1.711 + sum_(0),
1.712 + sum_squares_(0),
1.713 + log_sum_(0),
1.714 + log_sum_squares_(0),
1.715 + redundant_count_(0) {
1.716 +}
1.717 +
1.718 +Histogram::SampleSet::~SampleSet() {
1.719 +}
1.720 +
1.721 +void Histogram::SampleSet::Resize(const Histogram& histogram) {
1.722 + counts_.resize(histogram.bucket_count(), 0);
1.723 +}
1.724 +
1.725 +void Histogram::SampleSet::CheckSize(const Histogram& histogram) const {
1.726 + DCHECK_EQ(histogram.bucket_count(), counts_.size());
1.727 +}
1.728 +
1.729 +void Histogram::SampleSet::Accumulate(Sample value, Count count,
1.730 + size_t index) {
1.731 + DCHECK(count == 1 || count == -1);
1.732 + counts_[index] += count;
1.733 + redundant_count_ += count;
1.734 + sum_ += static_cast<int64_t>(count) * value;
1.735 + DCHECK_GE(counts_[index], 0);
1.736 + DCHECK_GE(sum_, 0);
1.737 + DCHECK_GE(redundant_count_, 0);
1.738 +}
1.739 +
1.740 +void Histogram::SampleSet::AccumulateWithLinearStats(Sample value,
1.741 + Count count,
1.742 + size_t index) {
1.743 + Accumulate(value, count, index);
1.744 + sum_squares_ += static_cast<int64_t>(count) * value * value;
1.745 +}
1.746 +
1.747 +void Histogram::SampleSet::AccumulateWithExponentialStats(Sample value,
1.748 + Count count,
1.749 + size_t index,
1.750 + bool computeExtendedStatistics) {
1.751 + Accumulate(value, count, index);
1.752 + if (computeExtendedStatistics) {
1.753 + DCHECK_GE(value, 0);
1.754 + float value_log = logf(static_cast<float>(value) + 1.0f);
1.755 + log_sum_ += count * value_log;
1.756 + log_sum_squares_ += count * value_log * value_log;
1.757 + }
1.758 +}
1.759 +
1.760 +Count Histogram::SampleSet::TotalCount() const {
1.761 + Count total = 0;
1.762 + for (Counts::const_iterator it = counts_.begin();
1.763 + it != counts_.end();
1.764 + ++it) {
1.765 + total += *it;
1.766 + }
1.767 + return total;
1.768 +}
1.769 +
1.770 +void Histogram::SampleSet::Add(const SampleSet& other) {
1.771 + DCHECK_EQ(counts_.size(), other.counts_.size());
1.772 + sum_ += other.sum_;
1.773 + sum_squares_ += other.sum_squares_;
1.774 + log_sum_ += other.log_sum_;
1.775 + log_sum_squares_ += other.log_sum_squares_;
1.776 + redundant_count_ += other.redundant_count_;
1.777 + for (size_t index = 0; index < counts_.size(); ++index)
1.778 + counts_[index] += other.counts_[index];
1.779 +}
1.780 +
1.781 +void Histogram::SampleSet::Subtract(const SampleSet& other) {
1.782 + DCHECK_EQ(counts_.size(), other.counts_.size());
1.783 + // Note: Race conditions in snapshotting a sum may lead to (temporary)
1.784 + // negative values when snapshots are later combined (and deltas calculated).
1.785 + // As a result, we don't currently CHCEK() for positive values.
1.786 + sum_ -= other.sum_;
1.787 + sum_squares_ -= other.sum_squares_;
1.788 + log_sum_ -= other.log_sum_;
1.789 + log_sum_squares_ -= other.log_sum_squares_;
1.790 + redundant_count_ -= other.redundant_count_;
1.791 + for (size_t index = 0; index < counts_.size(); ++index) {
1.792 + counts_[index] -= other.counts_[index];
1.793 + DCHECK_GE(counts_[index], 0);
1.794 + }
1.795 +}
1.796 +
1.797 +bool Histogram::SampleSet::Serialize(Pickle* pickle) const {
1.798 + pickle->WriteInt64(sum_);
1.799 + pickle->WriteInt64(redundant_count_);
1.800 + pickle->WriteSize(counts_.size());
1.801 +
1.802 + for (size_t index = 0; index < counts_.size(); ++index) {
1.803 + pickle->WriteInt(counts_[index]);
1.804 + }
1.805 +
1.806 + return true;
1.807 +}
1.808 +
1.809 +bool Histogram::SampleSet::Deserialize(void** iter, const Pickle& pickle) {
1.810 + DCHECK_EQ(counts_.size(), 0u);
1.811 + DCHECK_EQ(sum_, 0);
1.812 + DCHECK_EQ(redundant_count_, 0);
1.813 +
1.814 + size_t counts_size;
1.815 +
1.816 + if (!pickle.ReadInt64(iter, &sum_) ||
1.817 + !pickle.ReadInt64(iter, &redundant_count_) ||
1.818 + !pickle.ReadSize(iter, &counts_size)) {
1.819 + return false;
1.820 + }
1.821 +
1.822 + if (counts_size == 0)
1.823 + return false;
1.824 +
1.825 + int count = 0;
1.826 + for (size_t index = 0; index < counts_size; ++index) {
1.827 + int i;
1.828 + if (!pickle.ReadInt(iter, &i))
1.829 + return false;
1.830 + counts_.push_back(i);
1.831 + count += i;
1.832 + }
1.833 +
1.834 + return true;
1.835 +}
1.836 +
1.837 +//------------------------------------------------------------------------------
1.838 +// LinearHistogram: This histogram uses a traditional set of evenly spaced
1.839 +// buckets.
1.840 +//------------------------------------------------------------------------------
1.841 +
1.842 +LinearHistogram::~LinearHistogram() {
1.843 +}
1.844 +
1.845 +Histogram* LinearHistogram::FactoryGet(const std::string& name,
1.846 + Sample minimum,
1.847 + Sample maximum,
1.848 + size_t bucket_count,
1.849 + Flags flags) {
1.850 + Histogram* histogram(NULL);
1.851 +
1.852 + if (minimum < 1)
1.853 + minimum = 1;
1.854 + if (maximum > kSampleType_MAX - 1)
1.855 + maximum = kSampleType_MAX - 1;
1.856 +
1.857 + if (!StatisticsRecorder::FindHistogram(name, &histogram)) {
1.858 + LinearHistogram* tentative_histogram =
1.859 + new LinearHistogram(name, minimum, maximum, bucket_count);
1.860 + tentative_histogram->InitializeBucketRange();
1.861 + tentative_histogram->SetFlags(flags);
1.862 + histogram =
1.863 + StatisticsRecorder::RegisterOrDeleteDuplicate(tentative_histogram);
1.864 + }
1.865 +
1.866 + DCHECK_EQ(LINEAR_HISTOGRAM, histogram->histogram_type());
1.867 + DCHECK(histogram->HasConstructorArguments(minimum, maximum, bucket_count));
1.868 + return histogram;
1.869 +}
1.870 +
1.871 +Histogram* LinearHistogram::FactoryTimeGet(const std::string& name,
1.872 + TimeDelta minimum,
1.873 + TimeDelta maximum,
1.874 + size_t bucket_count,
1.875 + Flags flags) {
1.876 + return FactoryGet(name, minimum.InMilliseconds(), maximum.InMilliseconds(),
1.877 + bucket_count, flags);
1.878 +}
1.879 +
1.880 +Histogram::ClassType LinearHistogram::histogram_type() const {
1.881 + return LINEAR_HISTOGRAM;
1.882 +}
1.883 +
1.884 +void LinearHistogram::Accumulate(Sample value, Count count, size_t index) {
1.885 + sample_.AccumulateWithLinearStats(value, count, index);
1.886 +}
1.887 +
1.888 +void LinearHistogram::SetRangeDescriptions(
1.889 + const DescriptionPair descriptions[]) {
1.890 + for (int i =0; descriptions[i].description; ++i) {
1.891 + bucket_description_[descriptions[i].sample] = descriptions[i].description;
1.892 + }
1.893 +}
1.894 +
1.895 +LinearHistogram::LinearHistogram(const std::string& name,
1.896 + Sample minimum,
1.897 + Sample maximum,
1.898 + size_t bucket_count)
1.899 + : Histogram(name, minimum >= 1 ? minimum : 1, maximum, bucket_count) {
1.900 +}
1.901 +
1.902 +LinearHistogram::LinearHistogram(const std::string& name,
1.903 + TimeDelta minimum,
1.904 + TimeDelta maximum,
1.905 + size_t bucket_count)
1.906 + : Histogram(name, minimum >= TimeDelta::FromMilliseconds(1) ?
1.907 + minimum : TimeDelta::FromMilliseconds(1),
1.908 + maximum, bucket_count) {
1.909 +}
1.910 +
1.911 +void LinearHistogram::InitializeBucketRange() {
1.912 + DCHECK_GT(declared_min(), 0); // 0 is the underflow bucket here.
1.913 + double min = declared_min();
1.914 + double max = declared_max();
1.915 + size_t i;
1.916 + for (i = 1; i < bucket_count(); ++i) {
1.917 + double linear_range = (min * (bucket_count() -1 - i) + max * (i - 1)) /
1.918 + (bucket_count() - 2);
1.919 + SetBucketRange(i, static_cast<int> (linear_range + 0.5));
1.920 + }
1.921 + ResetRangeChecksum();
1.922 +}
1.923 +
1.924 +double LinearHistogram::GetBucketSize(Count current, size_t i) const {
1.925 + DCHECK_GT(ranges(i + 1), ranges(i));
1.926 + // Adjacent buckets with different widths would have "surprisingly" many (few)
1.927 + // samples in a histogram if we didn't normalize this way.
1.928 + double denominator = ranges(i + 1) - ranges(i);
1.929 + return current/denominator;
1.930 +}
1.931 +
1.932 +const std::string LinearHistogram::GetAsciiBucketRange(size_t i) const {
1.933 + int range = ranges(i);
1.934 + BucketDescriptionMap::const_iterator it = bucket_description_.find(range);
1.935 + if (it == bucket_description_.end())
1.936 + return Histogram::GetAsciiBucketRange(i);
1.937 + return it->second;
1.938 +}
1.939 +
1.940 +bool LinearHistogram::PrintEmptyBucket(size_t index) const {
1.941 + return bucket_description_.find(ranges(index)) == bucket_description_.end();
1.942 +}
1.943 +
1.944 +
1.945 +//------------------------------------------------------------------------------
1.946 +// This section provides implementation for BooleanHistogram.
1.947 +//------------------------------------------------------------------------------
1.948 +
1.949 +Histogram* BooleanHistogram::FactoryGet(const std::string& name, Flags flags) {
1.950 + Histogram* histogram(NULL);
1.951 +
1.952 + if (!StatisticsRecorder::FindHistogram(name, &histogram)) {
1.953 + BooleanHistogram* tentative_histogram = new BooleanHistogram(name);
1.954 + tentative_histogram->InitializeBucketRange();
1.955 + tentative_histogram->SetFlags(flags);
1.956 + histogram =
1.957 + StatisticsRecorder::RegisterOrDeleteDuplicate(tentative_histogram);
1.958 + }
1.959 +
1.960 + DCHECK_EQ(BOOLEAN_HISTOGRAM, histogram->histogram_type());
1.961 + return histogram;
1.962 +}
1.963 +
1.964 +Histogram::ClassType BooleanHistogram::histogram_type() const {
1.965 + return BOOLEAN_HISTOGRAM;
1.966 +}
1.967 +
1.968 +void BooleanHistogram::AddBoolean(bool value) {
1.969 + Add(value ? 1 : 0);
1.970 +}
1.971 +
1.972 +BooleanHistogram::BooleanHistogram(const std::string& name)
1.973 + : LinearHistogram(name, 1, 2, 3) {
1.974 +}
1.975 +
1.976 +void
1.977 +BooleanHistogram::Accumulate(Sample value, Count count, size_t index)
1.978 +{
1.979 + // Callers will have computed index based on the non-booleanified value.
1.980 + // So we need to adjust the index manually.
1.981 + LinearHistogram::Accumulate(!!value, count, value ? 1 : 0);
1.982 +}
1.983 +
1.984 +//------------------------------------------------------------------------------
1.985 +// FlagHistogram:
1.986 +//------------------------------------------------------------------------------
1.987 +
1.988 +Histogram *
1.989 +FlagHistogram::FactoryGet(const std::string &name, Flags flags)
1.990 +{
1.991 + Histogram *h(nullptr);
1.992 +
1.993 + if (!StatisticsRecorder::FindHistogram(name, &h)) {
1.994 + FlagHistogram *fh = new FlagHistogram(name);
1.995 + fh->InitializeBucketRange();
1.996 + fh->SetFlags(flags);
1.997 + size_t zero_index = fh->BucketIndex(0);
1.998 + fh->LinearHistogram::Accumulate(0, 1, zero_index);
1.999 + h = StatisticsRecorder::RegisterOrDeleteDuplicate(fh);
1.1000 + }
1.1001 +
1.1002 + return h;
1.1003 +}
1.1004 +
1.1005 +FlagHistogram::FlagHistogram(const std::string &name)
1.1006 + : BooleanHistogram(name), mSwitched(false) {
1.1007 +}
1.1008 +
1.1009 +Histogram::ClassType
1.1010 +FlagHistogram::histogram_type() const
1.1011 +{
1.1012 + return FLAG_HISTOGRAM;
1.1013 +}
1.1014 +
1.1015 +void
1.1016 +FlagHistogram::Accumulate(Sample value, Count count, size_t index)
1.1017 +{
1.1018 + if (mSwitched) {
1.1019 + return;
1.1020 + }
1.1021 +
1.1022 + mSwitched = true;
1.1023 + DCHECK_EQ(value, 1);
1.1024 + LinearHistogram::Accumulate(value, 1, index);
1.1025 + size_t zero_index = BucketIndex(0);
1.1026 + LinearHistogram::Accumulate(0, -1, zero_index);
1.1027 +}
1.1028 +
1.1029 +void
1.1030 +FlagHistogram::AddSampleSet(const SampleSet& sample) {
1.1031 + DCHECK_EQ(bucket_count(), sample.size());
1.1032 + // We can't be sure the SampleSet provided came from another FlagHistogram,
1.1033 + // so we take the following steps:
1.1034 + // - If our flag has already been set do nothing.
1.1035 + // - Set our flag if the following hold:
1.1036 + // - The sum of the counts in the provided SampleSet is 1.
1.1037 + // - The bucket index for that single value is the same as the index where we
1.1038 + // would place our set flag.
1.1039 + // - Otherwise, take no action.
1.1040 +
1.1041 + if (mSwitched) {
1.1042 + return;
1.1043 + }
1.1044 +
1.1045 + if (sample.sum() != 1) {
1.1046 + return;
1.1047 + }
1.1048 +
1.1049 + size_t one_index = BucketIndex(1);
1.1050 + if (sample.counts(one_index) == 1) {
1.1051 + Accumulate(1, 1, one_index);
1.1052 + }
1.1053 +}
1.1054 +//------------------------------------------------------------------------------
1.1055 +// CustomHistogram:
1.1056 +//------------------------------------------------------------------------------
1.1057 +
1.1058 +Histogram* CustomHistogram::FactoryGet(const std::string& name,
1.1059 + const std::vector<Sample>& custom_ranges,
1.1060 + Flags flags) {
1.1061 + Histogram* histogram(NULL);
1.1062 +
1.1063 + // Remove the duplicates in the custom ranges array.
1.1064 + std::vector<int> ranges = custom_ranges;
1.1065 + ranges.push_back(0); // Ensure we have a zero value.
1.1066 + std::sort(ranges.begin(), ranges.end());
1.1067 + ranges.erase(std::unique(ranges.begin(), ranges.end()), ranges.end());
1.1068 + if (ranges.size() <= 1) {
1.1069 + DCHECK(false);
1.1070 + // Note that we pushed a 0 in above, so for defensive code....
1.1071 + ranges.push_back(1); // Put in some data so we can index to [1].
1.1072 + }
1.1073 +
1.1074 + DCHECK_LT(ranges.back(), kSampleType_MAX);
1.1075 +
1.1076 + if (!StatisticsRecorder::FindHistogram(name, &histogram)) {
1.1077 + CustomHistogram* tentative_histogram = new CustomHistogram(name, ranges);
1.1078 + tentative_histogram->InitializedCustomBucketRange(ranges);
1.1079 + tentative_histogram->SetFlags(flags);
1.1080 + histogram =
1.1081 + StatisticsRecorder::RegisterOrDeleteDuplicate(tentative_histogram);
1.1082 + }
1.1083 +
1.1084 + DCHECK_EQ(histogram->histogram_type(), CUSTOM_HISTOGRAM);
1.1085 + DCHECK(histogram->HasConstructorArguments(ranges[1], ranges.back(),
1.1086 + ranges.size()));
1.1087 + return histogram;
1.1088 +}
1.1089 +
1.1090 +Histogram::ClassType CustomHistogram::histogram_type() const {
1.1091 + return CUSTOM_HISTOGRAM;
1.1092 +}
1.1093 +
1.1094 +CustomHistogram::CustomHistogram(const std::string& name,
1.1095 + const std::vector<Sample>& custom_ranges)
1.1096 + : Histogram(name, custom_ranges[1], custom_ranges.back(),
1.1097 + custom_ranges.size()) {
1.1098 + DCHECK_GT(custom_ranges.size(), 1u);
1.1099 + DCHECK_EQ(custom_ranges[0], 0);
1.1100 +}
1.1101 +
1.1102 +void CustomHistogram::InitializedCustomBucketRange(
1.1103 + const std::vector<Sample>& custom_ranges) {
1.1104 + DCHECK_GT(custom_ranges.size(), 1u);
1.1105 + DCHECK_EQ(custom_ranges[0], 0);
1.1106 + DCHECK_LE(custom_ranges.size(), bucket_count());
1.1107 + for (size_t index = 0; index < custom_ranges.size(); ++index)
1.1108 + SetBucketRange(index, custom_ranges[index]);
1.1109 + ResetRangeChecksum();
1.1110 +}
1.1111 +
1.1112 +double CustomHistogram::GetBucketSize(Count current, size_t i) const {
1.1113 + return 1;
1.1114 +}
1.1115 +
1.1116 +//------------------------------------------------------------------------------
1.1117 +// The next section handles global (central) support for all histograms, as well
1.1118 +// as startup/teardown of this service.
1.1119 +//------------------------------------------------------------------------------
1.1120 +
1.1121 +// This singleton instance should be started during the single threaded portion
1.1122 +// of main(), and hence it is not thread safe. It initializes globals to
1.1123 +// provide support for all future calls.
1.1124 +StatisticsRecorder::StatisticsRecorder() {
1.1125 + DCHECK(!histograms_);
1.1126 + if (lock_ == NULL) {
1.1127 + // This will leak on purpose. It's the only way to make sure we won't race
1.1128 + // against the static uninitialization of the module while one of our
1.1129 + // static methods relying on the lock get called at an inappropriate time
1.1130 + // during the termination phase. Since it's a static data member, we will
1.1131 + // leak one per process, which would be similar to the instance allocated
1.1132 + // during static initialization and released only on process termination.
1.1133 + lock_ = new base::Lock;
1.1134 + }
1.1135 + base::AutoLock auto_lock(*lock_);
1.1136 + histograms_ = new HistogramMap;
1.1137 +}
1.1138 +
1.1139 +StatisticsRecorder::~StatisticsRecorder() {
1.1140 + DCHECK(histograms_ && lock_);
1.1141 +
1.1142 + if (dump_on_exit_) {
1.1143 + std::string output;
1.1144 + WriteGraph("", &output);
1.1145 + CHROMIUM_LOG(INFO) << output;
1.1146 + }
1.1147 + // Clean up.
1.1148 + HistogramMap* histograms = NULL;
1.1149 + {
1.1150 + base::AutoLock auto_lock(*lock_);
1.1151 + histograms = histograms_;
1.1152 + histograms_ = NULL;
1.1153 + for (HistogramMap::iterator it = histograms->begin();
1.1154 + histograms->end() != it;
1.1155 + ++it) {
1.1156 + // No other clients permanently hold Histogram references, so we
1.1157 + // have the only one and it is safe to delete it.
1.1158 + delete it->second;
1.1159 + }
1.1160 + }
1.1161 + delete histograms;
1.1162 + // We don't delete lock_ on purpose to avoid having to properly protect
1.1163 + // against it going away after we checked for NULL in the static methods.
1.1164 +}
1.1165 +
1.1166 +// static
1.1167 +bool StatisticsRecorder::IsActive() {
1.1168 + if (lock_ == NULL)
1.1169 + return false;
1.1170 + base::AutoLock auto_lock(*lock_);
1.1171 + return NULL != histograms_;
1.1172 +}
1.1173 +
1.1174 +Histogram* StatisticsRecorder::RegisterOrDeleteDuplicate(Histogram* histogram) {
1.1175 + DCHECK(histogram->HasValidRangeChecksum());
1.1176 + if (lock_ == NULL)
1.1177 + return histogram;
1.1178 + base::AutoLock auto_lock(*lock_);
1.1179 + if (!histograms_)
1.1180 + return histogram;
1.1181 + const std::string name = histogram->histogram_name();
1.1182 + HistogramMap::iterator it = histograms_->find(name);
1.1183 + // Avoid overwriting a previous registration.
1.1184 + if (histograms_->end() == it) {
1.1185 + (*histograms_)[name] = histogram;
1.1186 + } else {
1.1187 + delete histogram; // We already have one by this name.
1.1188 + histogram = it->second;
1.1189 + }
1.1190 + return histogram;
1.1191 +}
1.1192 +
1.1193 +// static
1.1194 +void StatisticsRecorder::WriteHTMLGraph(const std::string& query,
1.1195 + std::string* output) {
1.1196 + if (!IsActive())
1.1197 + return;
1.1198 + output->append("<html><head><title>About Histograms");
1.1199 + if (!query.empty())
1.1200 + output->append(" - " + query);
1.1201 + output->append("</title>"
1.1202 + // We'd like the following no-cache... but it doesn't work.
1.1203 + // "<META HTTP-EQUIV=\"Pragma\" CONTENT=\"no-cache\">"
1.1204 + "</head><body>");
1.1205 +
1.1206 + Histograms snapshot;
1.1207 + GetSnapshot(query, &snapshot);
1.1208 + for (Histograms::iterator it = snapshot.begin();
1.1209 + it != snapshot.end();
1.1210 + ++it) {
1.1211 + (*it)->WriteHTMLGraph(output);
1.1212 + output->append("<br><hr><br>");
1.1213 + }
1.1214 + output->append("</body></html>");
1.1215 +}
1.1216 +
1.1217 +// static
1.1218 +void StatisticsRecorder::WriteGraph(const std::string& query,
1.1219 + std::string* output) {
1.1220 + if (!IsActive())
1.1221 + return;
1.1222 + if (query.length())
1.1223 + StringAppendF(output, "Collections of histograms for %s\n", query.c_str());
1.1224 + else
1.1225 + output->append("Collections of all histograms\n");
1.1226 +
1.1227 + Histograms snapshot;
1.1228 + GetSnapshot(query, &snapshot);
1.1229 + for (Histograms::iterator it = snapshot.begin();
1.1230 + it != snapshot.end();
1.1231 + ++it) {
1.1232 + (*it)->WriteAscii(true, "\n", output);
1.1233 + output->append("\n");
1.1234 + }
1.1235 +}
1.1236 +
1.1237 +// static
1.1238 +void StatisticsRecorder::GetHistograms(Histograms* output) {
1.1239 + if (lock_ == NULL)
1.1240 + return;
1.1241 + base::AutoLock auto_lock(*lock_);
1.1242 + if (!histograms_)
1.1243 + return;
1.1244 + for (HistogramMap::iterator it = histograms_->begin();
1.1245 + histograms_->end() != it;
1.1246 + ++it) {
1.1247 + DCHECK_EQ(it->first, it->second->histogram_name());
1.1248 + output->push_back(it->second);
1.1249 + }
1.1250 +}
1.1251 +
1.1252 +bool StatisticsRecorder::FindHistogram(const std::string& name,
1.1253 + Histogram** histogram) {
1.1254 + if (lock_ == NULL)
1.1255 + return false;
1.1256 + base::AutoLock auto_lock(*lock_);
1.1257 + if (!histograms_)
1.1258 + return false;
1.1259 + HistogramMap::iterator it = histograms_->find(name);
1.1260 + if (histograms_->end() == it)
1.1261 + return false;
1.1262 + *histogram = it->second;
1.1263 + return true;
1.1264 +}
1.1265 +
1.1266 +// private static
1.1267 +void StatisticsRecorder::GetSnapshot(const std::string& query,
1.1268 + Histograms* snapshot) {
1.1269 + if (lock_ == NULL)
1.1270 + return;
1.1271 + base::AutoLock auto_lock(*lock_);
1.1272 + if (!histograms_)
1.1273 + return;
1.1274 + for (HistogramMap::iterator it = histograms_->begin();
1.1275 + histograms_->end() != it;
1.1276 + ++it) {
1.1277 + if (it->first.find(query) != std::string::npos)
1.1278 + snapshot->push_back(it->second);
1.1279 + }
1.1280 +}
1.1281 +
1.1282 +// static
1.1283 +StatisticsRecorder::HistogramMap* StatisticsRecorder::histograms_ = NULL;
1.1284 +// static
1.1285 +base::Lock* StatisticsRecorder::lock_ = NULL;
1.1286 +// static
1.1287 +bool StatisticsRecorder::dump_on_exit_ = false;
1.1288 +
1.1289 +} // namespace base
