github.com/SagerNet/gvisor@v0.0.0-20210707092255-7731c139d75c/test/perf/linux/write_benchmark.cc (about)

     1  // Copyright 2020 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  #include <fcntl.h>
    16  #include <stdlib.h>
    17  #include <sys/stat.h>
    18  #include <unistd.h>
    19  
    20  #include "gtest/gtest.h"
    21  #include "benchmark/benchmark.h"
    22  #include "test/util/logging.h"
    23  #include "test/util/temp_path.h"
    24  #include "test/util/test_util.h"
    25  
    26  namespace gvisor {
    27  namespace testing {
    28  
    29  namespace {
    30  
    31  void BM_Write(benchmark::State& state) {
    32    auto f = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile());
    33    FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(f.path(), O_WRONLY));
    34  
    35    const int size = state.range(0);
    36    std::vector<char> buf(size);
    37    RandomizeBuffer(buf.data(), size);
    38  
    39    for (auto _ : state) {
    40      TEST_CHECK(PwriteFd(fd.get(), buf.data(), size, 0) == size);
    41    }
    42  
    43    state.SetBytesProcessed(static_cast<int64_t>(size) *
    44                            static_cast<int64_t>(state.iterations()));
    45  }
    46  
    47  BENCHMARK(BM_Write)->Range(1, 1 << 26)->UseRealTime();
    48  
    49  void BM_Append(benchmark::State& state) {
    50    auto file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile());
    51    auto fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_WRONLY | O_APPEND));
    52  
    53    const char data = 'a';
    54    for (auto _ : state) {
    55      TEST_CHECK(WriteFd(fd.get(), &data, 1) == 1);
    56    }
    57  }
    58  
    59  BENCHMARK(BM_Append);
    60  
    61  }  // namespace
    62  
    63  }  // namespace testing
    64  }  // namespace gvisor