From 897ea01d5ffa4204f1a58353e7cb6e1bbdf096aa Mon Sep 17 00:00:00 2001
From: Ryan Schneider <ryanleeschneider@gmail.com>
Date: Thu, 14 Jun 2018 09:58:44 -0400
Subject: [PATCH] internal/debug: use pprof goroutine writer for debug_stacks
 (#16892)

* debug: Use pprof goroutine writer in debug.Stacks() to ensure all goroutines are captured.

* Up to 64MB limit, previous code only captured first 1MB of goroutines.

* internal/debug: simplify stacks handler

* fix typo

* fix pointer receiver
---
 internal/debug/api.go | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/internal/debug/api.go b/internal/debug/api.go
index 048b7d7635..86a4218f6a 100644
--- a/internal/debug/api.go
+++ b/internal/debug/api.go
@@ -21,6 +21,7 @@
 package debug
 
 import (
+	"bytes"
 	"errors"
 	"io"
 	"os"
@@ -190,9 +191,9 @@ func (*HandlerT) WriteMemProfile(file string) error {
 
 // Stacks returns a printed representation of the stacks of all goroutines.
 func (*HandlerT) Stacks() string {
-	buf := make([]byte, 1024*1024)
-	buf = buf[:runtime.Stack(buf, true)]
-	return string(buf)
+	buf := new(bytes.Buffer)
+	pprof.Lookup("goroutine").WriteTo(buf, 2)
+	return buf.String()
 }
 
 // FreeOSMemory returns unused memory to the OS.