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-rw-r--r--test/perf/linux/fork_benchmark.cc350
1 files changed, 0 insertions, 350 deletions
diff --git a/test/perf/linux/fork_benchmark.cc b/test/perf/linux/fork_benchmark.cc
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index 84fdbc8a0..000000000
--- a/test/perf/linux/fork_benchmark.cc
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@@ -1,350 +0,0 @@
-// Copyright 2020 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#include <unistd.h>
-
-#include "gtest/gtest.h"
-#include "absl/synchronization/barrier.h"
-#include "benchmark/benchmark.h"
-#include "test/util/cleanup.h"
-#include "test/util/file_descriptor.h"
-#include "test/util/logging.h"
-#include "test/util/test_util.h"
-#include "test/util/thread_util.h"
-
-namespace gvisor {
-namespace testing {
-
-namespace {
-
-constexpr int kBusyMax = 250;
-
-// Do some CPU-bound busy-work.
-int busy(int max) {
- // Prevent the compiler from optimizing this work away,
- volatile int count = 0;
-
- for (int i = 1; i < max; i++) {
- for (int j = 2; j < i / 2; j++) {
- if (i % j == 0) {
- count++;
- }
- }
- }
-
- return count;
-}
-
-void BM_CPUBoundUniprocess(benchmark::State& state) {
- for (auto _ : state) {
- busy(kBusyMax);
- }
-}
-
-BENCHMARK(BM_CPUBoundUniprocess);
-
-void BM_CPUBoundAsymmetric(benchmark::State& state) {
- const size_t max = state.max_iterations;
- pid_t child = fork();
- if (child == 0) {
- for (int i = 0; i < max; i++) {
- busy(kBusyMax);
- }
- _exit(0);
- }
- ASSERT_THAT(child, SyscallSucceeds());
- ASSERT_TRUE(state.KeepRunningBatch(max));
-
- int status;
- EXPECT_THAT(RetryEINTR(waitpid)(child, &status, 0), SyscallSucceeds());
- EXPECT_TRUE(WIFEXITED(status));
- EXPECT_EQ(0, WEXITSTATUS(status));
- ASSERT_FALSE(state.KeepRunning());
-}
-
-BENCHMARK(BM_CPUBoundAsymmetric)->UseRealTime();
-
-void BM_CPUBoundSymmetric(benchmark::State& state) {
- std::vector<pid_t> children;
- auto child_cleanup = Cleanup([&] {
- for (const pid_t child : children) {
- int status;
- EXPECT_THAT(RetryEINTR(waitpid)(child, &status, 0), SyscallSucceeds());
- EXPECT_TRUE(WIFEXITED(status));
- EXPECT_EQ(0, WEXITSTATUS(status));
- }
- ASSERT_FALSE(state.KeepRunning());
- });
-
- const int processes = state.range(0);
- for (int i = 0; i < processes; i++) {
- size_t cur = (state.max_iterations + (processes - 1)) / processes;
- if ((state.iterations() + cur) >= state.max_iterations) {
- cur = state.max_iterations - state.iterations();
- }
- pid_t child = fork();
- if (child == 0) {
- for (int i = 0; i < cur; i++) {
- busy(kBusyMax);
- }
- _exit(0);
- }
- ASSERT_THAT(child, SyscallSucceeds());
- if (cur > 0) {
- // We can have a zero cur here, depending.
- ASSERT_TRUE(state.KeepRunningBatch(cur));
- }
- children.push_back(child);
- }
-}
-
-BENCHMARK(BM_CPUBoundSymmetric)->Range(2, 16)->UseRealTime();
-
-// Child routine for ProcessSwitch/ThreadSwitch.
-// Reads from readfd and writes the result to writefd.
-void SwitchChild(int readfd, int writefd) {
- while (1) {
- char buf;
- int ret = ReadFd(readfd, &buf, 1);
- if (ret == 0) {
- break;
- }
- TEST_CHECK_MSG(ret == 1, "read failed");
-
- ret = WriteFd(writefd, &buf, 1);
- if (ret == -1) {
- TEST_CHECK_MSG(errno == EPIPE, "unexpected write failure");
- break;
- }
- TEST_CHECK_MSG(ret == 1, "write failed");
- }
-}
-
-// Send bytes in a loop through a series of pipes, each passing through a
-// different process.
-//
-// Proc 0 Proc 1
-// * ----------> *
-// ^ Pipe 1 |
-// | |
-// | Pipe 0 | Pipe 2
-// | |
-// | |
-// | Pipe 3 v
-// * <---------- *
-// Proc 3 Proc 2
-//
-// This exercises context switching through multiple processes.
-void BM_ProcessSwitch(benchmark::State& state) {
- // Code below assumes there are at least two processes.
- const int num_processes = state.range(0);
- ASSERT_GE(num_processes, 2);
-
- std::vector<pid_t> children;
- auto child_cleanup = Cleanup([&] {
- for (const pid_t child : children) {
- int status;
- EXPECT_THAT(RetryEINTR(waitpid)(child, &status, 0), SyscallSucceeds());
- EXPECT_TRUE(WIFEXITED(status));
- EXPECT_EQ(0, WEXITSTATUS(status));
- }
- });
-
- // Must come after children, as the FDs must be closed before the children
- // will exit.
- std::vector<FileDescriptor> read_fds;
- std::vector<FileDescriptor> write_fds;
-
- for (int i = 0; i < num_processes; i++) {
- int fds[2];
- ASSERT_THAT(pipe(fds), SyscallSucceeds());
- read_fds.emplace_back(fds[0]);
- write_fds.emplace_back(fds[1]);
- }
-
- // This process is one of the processes in the loop. It will be considered
- // index 0.
- for (int i = 1; i < num_processes; i++) {
- // Read from current pipe index, write to next.
- const int read_index = i;
- const int read_fd = read_fds[read_index].get();
-
- const int write_index = (i + 1) % num_processes;
- const int write_fd = write_fds[write_index].get();
-
- // std::vector isn't safe to use from the fork child.
- FileDescriptor* read_array = read_fds.data();
- FileDescriptor* write_array = write_fds.data();
-
- pid_t child = fork();
- if (!child) {
- // Close all other FDs.
- for (int j = 0; j < num_processes; j++) {
- if (j != read_index) {
- read_array[j].reset();
- }
- if (j != write_index) {
- write_array[j].reset();
- }
- }
-
- SwitchChild(read_fd, write_fd);
- _exit(0);
- }
- ASSERT_THAT(child, SyscallSucceeds());
- children.push_back(child);
- }
-
- // Read from current pipe index (0), write to next (1).
- const int read_index = 0;
- const int read_fd = read_fds[read_index].get();
-
- const int write_index = 1;
- const int write_fd = write_fds[write_index].get();
-
- // Kick start the loop.
- char buf = 'a';
- ASSERT_THAT(WriteFd(write_fd, &buf, 1), SyscallSucceedsWithValue(1));
-
- for (auto _ : state) {
- ASSERT_THAT(ReadFd(read_fd, &buf, 1), SyscallSucceedsWithValue(1));
- ASSERT_THAT(WriteFd(write_fd, &buf, 1), SyscallSucceedsWithValue(1));
- }
-}
-
-BENCHMARK(BM_ProcessSwitch)->Range(2, 16)->UseRealTime();
-
-// Equivalent to BM_ThreadSwitch using threads instead of processes.
-void BM_ThreadSwitch(benchmark::State& state) {
- // Code below assumes there are at least two threads.
- const int num_threads = state.range(0);
- ASSERT_GE(num_threads, 2);
-
- // Must come after threads, as the FDs must be closed before the children
- // will exit.
- std::vector<std::unique_ptr<ScopedThread>> threads;
- std::vector<FileDescriptor> read_fds;
- std::vector<FileDescriptor> write_fds;
-
- for (int i = 0; i < num_threads; i++) {
- int fds[2];
- ASSERT_THAT(pipe(fds), SyscallSucceeds());
- read_fds.emplace_back(fds[0]);
- write_fds.emplace_back(fds[1]);
- }
-
- // This thread is one of the threads in the loop. It will be considered
- // index 0.
- for (int i = 1; i < num_threads; i++) {
- // Read from current pipe index, write to next.
- //
- // Transfer ownership of the FDs to the thread.
- const int read_index = i;
- const int read_fd = read_fds[read_index].release();
-
- const int write_index = (i + 1) % num_threads;
- const int write_fd = write_fds[write_index].release();
-
- threads.emplace_back(std::make_unique<ScopedThread>([read_fd, write_fd] {
- FileDescriptor read(read_fd);
- FileDescriptor write(write_fd);
- SwitchChild(read.get(), write.get());
- }));
- }
-
- // Read from current pipe index (0), write to next (1).
- const int read_index = 0;
- const int read_fd = read_fds[read_index].get();
-
- const int write_index = 1;
- const int write_fd = write_fds[write_index].get();
-
- // Kick start the loop.
- char buf = 'a';
- ASSERT_THAT(WriteFd(write_fd, &buf, 1), SyscallSucceedsWithValue(1));
-
- for (auto _ : state) {
- ASSERT_THAT(ReadFd(read_fd, &buf, 1), SyscallSucceedsWithValue(1));
- ASSERT_THAT(WriteFd(write_fd, &buf, 1), SyscallSucceedsWithValue(1));
- }
-
- // The two FDs still owned by this thread are closed, causing the next thread
- // to exit its loop and close its FDs, and so on until all threads exit.
-}
-
-BENCHMARK(BM_ThreadSwitch)->Range(2, 16)->UseRealTime();
-
-void BM_ThreadStart(benchmark::State& state) {
- const int num_threads = state.range(0);
-
- for (auto _ : state) {
- state.PauseTiming();
-
- auto barrier = new absl::Barrier(num_threads + 1);
- std::vector<std::unique_ptr<ScopedThread>> threads;
-
- state.ResumeTiming();
-
- for (size_t i = 0; i < num_threads; ++i) {
- threads.emplace_back(std::make_unique<ScopedThread>([barrier] {
- if (barrier->Block()) {
- delete barrier;
- }
- }));
- }
-
- if (barrier->Block()) {
- delete barrier;
- }
-
- state.PauseTiming();
-
- for (const auto& thread : threads) {
- thread->Join();
- }
-
- state.ResumeTiming();
- }
-}
-
-BENCHMARK(BM_ThreadStart)->Range(1, 2048)->UseRealTime();
-
-// Benchmark the complete fork + exit + wait.
-void BM_ProcessLifecycle(benchmark::State& state) {
- const int num_procs = state.range(0);
-
- std::vector<pid_t> pids(num_procs);
- for (auto _ : state) {
- for (size_t i = 0; i < num_procs; ++i) {
- int pid = fork();
- if (pid == 0) {
- _exit(0);
- }
- ASSERT_THAT(pid, SyscallSucceeds());
- pids[i] = pid;
- }
-
- for (const int pid : pids) {
- ASSERT_THAT(RetryEINTR(waitpid)(pid, nullptr, 0),
- SyscallSucceedsWithValue(pid));
- }
- }
-}
-
-BENCHMARK(BM_ProcessLifecycle)->Range(1, 512)->UseRealTime();
-
-} // namespace
-
-} // namespace testing
-} // namespace gvisor
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