// Start tracing.
	if err := trace.Start(os.Stdout); err != nil {
		log.Fatalf("failed to start tracing: %v", err)
	}
	// Run GOMAXPROCS a bunch of times, up and down.
	for i := 1; i <= 16; i *= 2 {
		runtime.GOMAXPROCS(i)
		time.Sleep(1 * time.Millisecond)
	}
	for i := 16; i >= 1; i /= 2 {
		runtime.GOMAXPROCS(i)
		time.Sleep(1 * time.Millisecond)
	}
	// Stop tracing.
	trace.Stop()

// blocked goroutines, LockOSThread, pipes, and GOMAXPROCS).

//go:build ignore

package main

import (
	"bytes"
	"io"
	"log"
	"net"
	"os"
	"runtime"
	"runtime/trace"
	"sync"
	"time"
)

func main() {
	defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(8))
	outerDone := make(chan bool)

	go func() {
		defer func() {
			outerDone <- true

// license that can be found in the LICENSE file.

// Tests a many interesting cases (network, syscalls, a little GC, busy goroutines,
// blocked goroutines, LockOSThread, pipes, and GOMAXPROCS).

//go:build ignore

package main

import (
	"log"
	"net"
	"os"
	"runtime"
	"runtime/trace"
	"sync"
	"time"
)

func main() {
	var wg sync.WaitGroup
	done := make(chan bool)

	if err != nil {
		log.Fatalf("failed to dial: %v", err)
	}
	c.Close()
	var data [1]byte
	wp.Write(data[:])
	<-pipeReadDone

	oldGoMaxProcs := runtime.GOMAXPROCS(0)
	runtime.GOMAXPROCS(oldGoMaxProcs + 1)

	trace.Stop()

	runtime.GOMAXPROCS(oldGoMaxProcs)

	"log"
	"os"
	"runtime"
	"runtime/trace"
	"sync"
)

func main() {
	if err := trace.Start(os.Stdout); err != nil {
		log.Fatalf("failed to start tracing: %v", err)
	}

	defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(8))
	c0 := make(chan int, 1)
	c1 := make(chan int, 1)
	c2 := make(chan int, 1)
	const procs = 2
	var done sync.WaitGroup
	done.Add(4 * procs)
	for p := 0; p < procs; p++ {
		const iters = 1e3

package runtime

import (
	"internal/runtime/atomic"
	"unsafe"
)

// GOMAXPROCS sets the maximum number of CPUs that can be executing
// simultaneously and returns the previous setting. It defaults to
// the value of [runtime.NumCPU]. If n < 1, it does not change the current setting.
// This call will go away when the scheduler improves.
func GOMAXPROCS(n int) int {
	if GOARCH == "wasm" && n > 1 {

func applyGCLoad(b *testing.B) func() {
	// We’ll apply load to the runtime with maxProcs-1 goroutines
	// and use one more to actually benchmark. It doesn't make sense
	// to try to run this test with only 1 P (that's what
	// BenchmarkReadMemStats is for).
	maxProcs := runtime.GOMAXPROCS(-1)
	if maxProcs == 1 {
		b.Skip("This benchmark can only be run with GOMAXPROCS > 1")
	}

	// Code to build a big tree with lots of pointers.

			// operations for now to begin with.
			if concurrency < 4 {
				concurrency = 4
			}

			// if GOMAXPROCS is set to a lower value then choose to use
			// concurrency == GOMAXPROCS instead.
			if runtime.GOMAXPROCS(0) < concurrency {
				concurrency = runtime.GOMAXPROCS(0)
			}
		}

		throughputHighestGet := uint64(0)
		throughputHighestPut := uint64(0)

			fn: func(t *testing.T) {
				runtime.GC()
			},
		},
		{
			name: "runtime.GOMAXPROCS",
			fn: func(t *testing.T) {
				if runtime.GOARCH == "wasm" {
					t.Skip("GOMAXPROCS >1 not supported on wasm")
				}

				n := runtime.GOMAXPROCS(0)
				defer runtime.GOMAXPROCS(n)

				runtime.GOMAXPROCS(n + 1)
			},
		},
		{
			name: "runtime.GoroutineProfile",
			fn: func(t *testing.T) {

	"github.com/klauspost/compress/s2"
	"github.com/klauspost/compress/zstd"
	gzip "github.com/klauspost/pgzip"
	"github.com/pierrec/lz4"
)

// Max bzip2 concurrency across calls. 50% of GOMAXPROCS.
var bz2Limiter = pbzip2.CreateConcurrencyPool((runtime.GOMAXPROCS(0) + 1) / 2)

func detect(r *bufio.Reader) format {
	z, err := r.Peek(4)
	if err != nil {
		return formatUnknown
	}
	for _, f := range magicHeaders {