runtime/pprof: document that debug=0 emits proto

Updates #16093.

Change-Id: I629b3d44d6b2083f5e62701cc0c23fe2362502d4
Reviewed-on: https://go-review.googlesource.com/c/go/+/222676
Reviewed-by: Michael Matloob <matloob@golang.org>

diff --git a/src/runtime/pprof/pprof.go b/src/runtime/pprof/pprof.go
index a7916bf6fb9d3fe213c1b1c2366750aa829e93fc..bbdc432eec4ca50025ce6ed973d4a90e55d3157a 100644 (file)
--- a/src/runtime/pprof/pprof.go
+++ b/src/runtime/pprof/pprof.go
@@ -313,9 +313,11 @@ func (p *Profile) Remove(value interface{}) {
 // Otherwise, WriteTo returns nil.
 //
 // The debug parameter enables additional output.
-// Passing debug=0 prints only the hexadecimal addresses that pprof needs.
-// Passing debug=1 adds comments translating addresses to function names
-// and line numbers, so that a programmer can read the profile without tools.
+// Passing debug=0 writes the gzip-compressed protocol buffer described
+// in https://github.com/google/pprof/tree/master/proto#overview.
+// Passing debug=1 writes the legacy text format with comments
+// translating addresses to function names and line numbers, so that a
+// programmer can read the profile without tools.
 //
 // The predefined profiles may assign meaning to other debug values;
 // for example, when printing the "goroutine" profile, debug=2 means to