| // Copyright 2023 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| // Tests user tasks, regions, and logging. |
| |
| //go:build ignore |
| |
| package main |
| |
| import ( |
| "context" |
| "fmt" |
| "log" |
| "os" |
| "runtime/trace" |
| "time" |
| ) |
| |
| func main() { |
| baseCtx := context.Background() |
| |
| // Create a task that starts and ends entirely outside of the trace. |
| ctx0, t0 := trace.NewTask(baseCtx, "parent") |
| |
| // Create a task that starts before the trace and ends during the trace. |
| ctx1, t1 := trace.NewTask(ctx0, "type1") |
| |
| // Start tracing. |
| if err := trace.Start(os.Stdout); err != nil { |
| log.Fatalf("failed to start tracing: %v", err) |
| } |
| t1.End() |
| |
| // Create a task that starts during the trace and ends after. |
| ctx2, t2 := trace.NewTask(ctx0, "type2") |
| |
| // Create a task that starts and ends during the trace. |
| ctx3, t3 := trace.NewTask(baseCtx, "type3") |
| |
| // Generate some events. |
| for i := 0; i < 2; i++ { |
| do(baseCtx, 4) |
| do(ctx0, 2) |
| do(ctx1, 3) |
| do(ctx2, 6) |
| do(ctx3, 5) |
| } |
| |
| // Finish up tasks according to their lifetime relative to the trace. |
| t3.End() |
| trace.Stop() |
| t2.End() |
| t0.End() |
| } |
| |
| func do(ctx context.Context, k int) { |
| trace.Log(ctx, "log", "before do") |
| |
| var t *trace.Task |
| ctx, t = trace.NewTask(ctx, "do") |
| defer t.End() |
| |
| trace.Log(ctx, "log2", "do") |
| |
| // Create a region and spawn more tasks and more workers. |
| trace.WithRegion(ctx, "fanout", func() { |
| for i := 0; i < k; i++ { |
| go func(i int) { |
| trace.WithRegion(ctx, fmt.Sprintf("region%d", i), func() { |
| trace.Logf(ctx, "log", "fanout region%d", i) |
| if i == 2 { |
| do(ctx, 0) |
| return |
| } |
| }) |
| }(i) |
| } |
| }) |
| |
| // Sleep to let things happen, but also increase the chance that we |
| // advance a generation. |
| time.Sleep(10 * time.Millisecond) |
| } |