folly/io/test/CompressionTest.cpp

   1 /*
   2  * Copyright 2017 Facebook, Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *   http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include <folly/io/Compression.h>
  18
  19 #include <random>
  20 #include <set>
  21 #include <thread>
  22 #include <unordered_map>
  23
  24 #include <boost/noncopyable.hpp>
  25 #include <glog/logging.h>
  26
  27 #include <folly/Benchmark.h>
  28 #include <folly/Hash.h>
  29 #include <folly/Random.h>
  30 #include <folly/Varint.h>
  31 #include <folly/io/IOBufQueue.h>
  32 #include <folly/portability/GTest.h>
  33
  34 namespace folly { namespace io { namespace test {
  35
  36 class DataHolder : private boost::noncopyable {
  37  public:
  38   uint64_t hash(size_t size) const;
  39   ByteRange data(size_t size) const;
  40
  41  protected:
  42   explicit DataHolder(size_t sizeLog2);
  43   const size_t size_;
  44   std::unique_ptr<uint8_t[]> data_;
  45   mutable std::unordered_map<uint64_t, uint64_t> hashCache_;
  46 };
  47
  48 DataHolder::DataHolder(size_t sizeLog2)
  49   : size_(size_t(1) << sizeLog2),
  50     data_(new uint8_t[size_]) {
  51 }
  52
  53 uint64_t DataHolder::hash(size_t size) const {
  54   CHECK_LE(size, size_);
  55   auto p = hashCache_.find(size);
  56   if (p != hashCache_.end()) {
  57     return p->second;
  58   }
  59
  60   uint64_t h = folly::hash::fnv64_buf(data_.get(), size);
  61   hashCache_[size] = h;
  62   return h;
  63 }
  64
  65 ByteRange DataHolder::data(size_t size) const {
  66   CHECK_LE(size, size_);
  67   return ByteRange(data_.get(), size);
  68 }
  69
  70 uint64_t hashIOBuf(const IOBuf* buf) {
  71   uint64_t h = folly::hash::FNV_64_HASH_START;
  72   for (auto& range : *buf) {
  73     h = folly::hash::fnv64_buf(range.data(), range.size(), h);
  74   }
  75   return h;
  76 }
  77
  78 class RandomDataHolder : public DataHolder {
  79  public:
  80   explicit RandomDataHolder(size_t sizeLog2);
  81 };
  82
  83 RandomDataHolder::RandomDataHolder(size_t sizeLog2)
  84   : DataHolder(sizeLog2) {
  85   constexpr size_t numThreadsLog2 = 3;
  86   constexpr size_t numThreads = size_t(1) << numThreadsLog2;
  87
  88   uint32_t seed = randomNumberSeed();
  89
  90   std::vector<std::thread> threads;
  91   threads.reserve(numThreads);
  92   for (size_t t = 0; t < numThreads; ++t) {
  93     threads.emplace_back(
  94         [this, seed, t, numThreadsLog2, sizeLog2] () {
  95           std::mt19937 rng(seed + t);
  96           size_t countLog2 = sizeLog2 - numThreadsLog2;
  97           size_t start = size_t(t) << countLog2;
  98           for (size_t i = 0; i < countLog2; ++i) {
  99             this->data_[start + i] = rng();
 100           }
 101         });
 102   }
 103
 104   for (auto& t : threads) {
 105     t.join();
 106   }
 107 }
 108
 109 class ConstantDataHolder : public DataHolder {
 110  public:
 111   explicit ConstantDataHolder(size_t sizeLog2);
 112 };
 113
 114 ConstantDataHolder::ConstantDataHolder(size_t sizeLog2)
 115   : DataHolder(sizeLog2) {
 116   memset(data_.get(), 'a', size_);
 117 }
 118
 119 constexpr size_t dataSizeLog2 = 27;  // 128MiB
 120 RandomDataHolder randomDataHolder(dataSizeLog2);
 121 ConstantDataHolder constantDataHolder(dataSizeLog2);
 122
 123 // The intersection of the provided codecs & those that are compiled in.
 124 static std::vector<CodecType> supportedCodecs(std::vector<CodecType> const& v) {
 125   std::vector<CodecType> supported;
 126
 127   std::copy_if(
 128       std::begin(v),
 129       std::end(v),
 130       std::back_inserter(supported),
 131       hasCodec);
 132
 133   return supported;
 134 }
 135
 136 // All compiled-in compression codecs.
 137 static std::vector<CodecType> availableCodecs() {
 138   std::vector<CodecType> codecs;
 139
 140   for (size_t i = 0; i < static_cast<size_t>(CodecType::NUM_CODEC_TYPES); ++i) {
 141     auto type = static_cast<CodecType>(i);
 142     if (hasCodec(type)) {
 143       codecs.push_back(type);
 144     }
 145   }
 146
 147   return codecs;
 148 }
 149
 150 TEST(CompressionTestNeedsUncompressedLength, Simple) {
 151   static const struct { CodecType type; bool needsUncompressedLength; }
 152     expectations[] = {
 153       { CodecType::NO_COMPRESSION, false },
 154       { CodecType::LZ4, true },
 155       { CodecType::SNAPPY, false },
 156       { CodecType::ZLIB, false },
 157       { CodecType::LZ4_VARINT_SIZE, false },
 158       { CodecType::LZMA2, true },
 159       { CodecType::LZMA2_VARINT_SIZE, false },
 160       { CodecType::ZSTD, false },
 161       { CodecType::GZIP, false },
 162     };
 163
 164   for (auto const& test : expectations) {
 165     if (hasCodec(test.type)) {
 166       EXPECT_EQ(getCodec(test.type)->needsUncompressedLength(),
 167                 test.needsUncompressedLength);
 168     }
 169   }
 170 }
 171
 172 class CompressionTest
 173     : public testing::TestWithParam<std::tr1::tuple<int, int, CodecType>> {
 174  protected:
 175   void SetUp() override {
 176     auto tup = GetParam();
 177     uncompressedLength_ = uint64_t(1) << std::tr1::get<0>(tup);
 178     chunks_ = std::tr1::get<1>(tup);
 179     codec_ = getCodec(std::tr1::get<2>(tup));
 180   }
 181
 182   void runSimpleIOBufTest(const DataHolder& dh);
 183
 184   void runSimpleStringTest(const DataHolder& dh);
 185
 186  private:
 187   std::unique_ptr<IOBuf> split(std::unique_ptr<IOBuf> data) const;
 188
 189   uint64_t uncompressedLength_;
 190   size_t chunks_;
 191   std::unique_ptr<Codec> codec_;
 192 };
 193
 194 void CompressionTest::runSimpleIOBufTest(const DataHolder& dh) {
 195   const auto original = split(IOBuf::wrapBuffer(dh.data(uncompressedLength_)));
 196   const auto compressed = split(codec_->compress(original.get()));
 197   if (!codec_->needsUncompressedLength()) {
 198     auto uncompressed = codec_->uncompress(compressed.get());
 199     EXPECT_EQ(uncompressedLength_, uncompressed->computeChainDataLength());
 200     EXPECT_EQ(dh.hash(uncompressedLength_), hashIOBuf(uncompressed.get()));
 201   }
 202   {
 203     auto uncompressed = codec_->uncompress(compressed.get(),
 204                                            uncompressedLength_);
 205     EXPECT_EQ(uncompressedLength_, uncompressed->computeChainDataLength());
 206     EXPECT_EQ(dh.hash(uncompressedLength_), hashIOBuf(uncompressed.get()));
 207   }
 208 }
 209
 210 void CompressionTest::runSimpleStringTest(const DataHolder& dh) {
 211   const auto original = std::string(
 212       reinterpret_cast<const char*>(dh.data(uncompressedLength_).data()),
 213       uncompressedLength_);
 214   const auto compressed = codec_->compress(original);
 215   if (!codec_->needsUncompressedLength()) {
 216     auto uncompressed = codec_->uncompress(compressed);
 217     EXPECT_EQ(uncompressedLength_, uncompressed.length());
 218     EXPECT_EQ(uncompressed, original);
 219   }
 220   {
 221     auto uncompressed = codec_->uncompress(compressed, uncompressedLength_);
 222     EXPECT_EQ(uncompressedLength_, uncompressed.length());
 223     EXPECT_EQ(uncompressed, original);
 224   }
 225 }
 226
 227 // Uniformly split data into (potentially empty) chunks.
 228 std::unique_ptr<IOBuf> CompressionTest::split(
 229     std::unique_ptr<IOBuf> data) const {
 230   if (data->isChained()) {
 231     data->coalesce();
 232   }
 233
 234   const size_t size = data->computeChainDataLength();
 235
 236   std::multiset<size_t> splits;
 237   for (size_t i = 1; i < chunks_; ++i) {
 238     splits.insert(Random::rand64(size));
 239   }
 240
 241   folly::IOBufQueue result;
 242
 243   size_t offset = 0;
 244   for (size_t split : splits) {
 245     result.append(IOBuf::copyBuffer(data->data() + offset, split - offset));
 246     offset = split;
 247   }
 248   result.append(IOBuf::copyBuffer(data->data() + offset, size - offset));
 249
 250   return result.move();
 251 }
 252
 253 TEST_P(CompressionTest, RandomData) {
 254   runSimpleIOBufTest(randomDataHolder);
 255 }
 256
 257 TEST_P(CompressionTest, ConstantData) {
 258   runSimpleIOBufTest(constantDataHolder);
 259 }
 260
 261 TEST_P(CompressionTest, RandomDataString) {
 262   runSimpleStringTest(randomDataHolder);
 263 }
 264
 265 TEST_P(CompressionTest, ConstantDataString) {
 266   runSimpleStringTest(constantDataHolder);
 267 }
 268
 269 INSTANTIATE_TEST_CASE_P(
 270     CompressionTest,
 271     CompressionTest,
 272     testing::Combine(
 273         testing::Values(0, 1, 12, 22, 25, 27),
 274         testing::Values(1, 2, 3, 8, 65),
 275         testing::ValuesIn(availableCodecs())));
 276
 277 class CompressionVarintTest
 278     : public testing::TestWithParam<std::tr1::tuple<int, CodecType>> {
 279  protected:
 280   void SetUp() override {
 281     auto tup = GetParam();
 282     uncompressedLength_ = uint64_t(1) << std::tr1::get<0>(tup);
 283     codec_ = getCodec(std::tr1::get<1>(tup));
 284   }
 285
 286   void runSimpleTest(const DataHolder& dh);
 287
 288   uint64_t uncompressedLength_;
 289   std::unique_ptr<Codec> codec_;
 290 };
 291
 292 inline uint64_t oneBasedMsbPos(uint64_t number) {
 293   uint64_t pos = 0;
 294   for (; number > 0; ++pos, number >>= 1) {
 295   }
 296   return pos;
 297 }
 298
 299 void CompressionVarintTest::runSimpleTest(const DataHolder& dh) {
 300   auto original = IOBuf::wrapBuffer(dh.data(uncompressedLength_));
 301   auto compressed = codec_->compress(original.get());
 302   auto breakPoint =
 303       1UL +
 304       Random::rand64(
 305           std::max(uint64_t(9), oneBasedMsbPos(uncompressedLength_)) / 9UL);
 306   auto tinyBuf = IOBuf::copyBuffer(compressed->data(),
 307                                    std::min(compressed->length(), breakPoint));
 308   compressed->trimStart(breakPoint);
 309   tinyBuf->prependChain(std::move(compressed));
 310   compressed = std::move(tinyBuf);
 311
 312   auto uncompressed = codec_->uncompress(compressed.get());
 313
 314   EXPECT_EQ(uncompressedLength_, uncompressed->computeChainDataLength());
 315   EXPECT_EQ(dh.hash(uncompressedLength_), hashIOBuf(uncompressed.get()));
 316 }
 317
 318 TEST_P(CompressionVarintTest, RandomData) {
 319   runSimpleTest(randomDataHolder);
 320 }
 321
 322 TEST_P(CompressionVarintTest, ConstantData) {
 323   runSimpleTest(constantDataHolder);
 324 }
 325
 326 INSTANTIATE_TEST_CASE_P(
 327     CompressionVarintTest,
 328     CompressionVarintTest,
 329     testing::Combine(
 330         testing::Values(0, 1, 12, 22, 25, 27),
 331         testing::ValuesIn(supportedCodecs({
 332             CodecType::LZ4_VARINT_SIZE,
 333             CodecType::LZMA2_VARINT_SIZE,
 334             }))));
 335
 336 class CompressionCorruptionTest : public testing::TestWithParam<CodecType> {
 337  protected:
 338   void SetUp() override { codec_ = getCodec(GetParam()); }
 339
 340   void runSimpleTest(const DataHolder& dh);
 341
 342   std::unique_ptr<Codec> codec_;
 343 };
 344
 345 void CompressionCorruptionTest::runSimpleTest(const DataHolder& dh) {
 346   constexpr uint64_t uncompressedLength = 42;
 347   auto original = IOBuf::wrapBuffer(dh.data(uncompressedLength));
 348   auto compressed = codec_->compress(original.get());
 349
 350   if (!codec_->needsUncompressedLength()) {
 351     auto uncompressed = codec_->uncompress(compressed.get());
 352     EXPECT_EQ(uncompressedLength, uncompressed->computeChainDataLength());
 353     EXPECT_EQ(dh.hash(uncompressedLength), hashIOBuf(uncompressed.get()));
 354   }
 355   {
 356     auto uncompressed = codec_->uncompress(compressed.get(),
 357                                            uncompressedLength);
 358     EXPECT_EQ(uncompressedLength, uncompressed->computeChainDataLength());
 359     EXPECT_EQ(dh.hash(uncompressedLength), hashIOBuf(uncompressed.get()));
 360   }
 361
 362   EXPECT_THROW(codec_->uncompress(compressed.get(), uncompressedLength + 1),
 363                std::runtime_error);
 364
 365   // Corrupt the first character
 366   ++(compressed->writableData()[0]);
 367
 368   if (!codec_->needsUncompressedLength()) {
 369     EXPECT_THROW(codec_->uncompress(compressed.get()),
 370                  std::runtime_error);
 371   }
 372
 373   EXPECT_THROW(codec_->uncompress(compressed.get(), uncompressedLength),
 374                std::runtime_error);
 375 }
 376
 377 TEST_P(CompressionCorruptionTest, RandomData) {
 378   runSimpleTest(randomDataHolder);
 379 }
 380
 381 TEST_P(CompressionCorruptionTest, ConstantData) {
 382   runSimpleTest(constantDataHolder);
 383 }
 384
 385 INSTANTIATE_TEST_CASE_P(
 386     CompressionCorruptionTest,
 387     CompressionCorruptionTest,
 388     testing::ValuesIn(
 389         // NO_COMPRESSION can't detect corruption
 390         // LZ4 can't detect corruption reliably (sigh)
 391         supportedCodecs({
 392             CodecType::SNAPPY,
 393             CodecType::ZLIB,
 394             })));
 395
 396 }}}  // namespaces
 397
 398 int main(int argc, char *argv[]) {
 399   testing::InitGoogleTest(&argc, argv);
 400   gflags::ParseCommandLineFlags(&argc, &argv, true);
 401
 402   auto ret = RUN_ALL_TESTS();
 403   if (!ret) {
 404     folly::runBenchmarksOnFlag();
 405   }
 406   return ret;
 407 }