perf(spanner): grab debug stack outside of lock (#11587)

egonelbre · rahul2393 · web-flow · commit 0ee82ff4ff38 · 2025-02-20T23:35:09.000+05:30
Co-authored-by: rahul2393 &lt;irahul@google.com&gt;
diff --git a/spanner/session.go b/spanner/session.go
@@ -1103,11 +1103,11 @@ func (p *sessionPool) newSessionHandle(s *session) (sh *sessionHandle) {
 		return sh
 	}
 	if p.TrackSessionHandles || p.ActionOnInactiveTransaction == Warn || p.ActionOnInactiveTransaction == WarnAndClose || p.ActionOnInactiveTransaction == Close {
-		p.mu.Lock()
-		sh.trackedSessionHandle = p.trackedSessionHandles.PushBack(sh)
 		if p.TrackSessionHandles {
 			sh.stack = debug.Stack()
 		}
+		p.mu.Lock()
+		sh.trackedSessionHandle = p.trackedSessionHandles.PushBack(sh)
 		p.mu.Unlock()
 	}
 	return sh

Original file line number	Diff line number	Diff line change
`@@ -1103,11 +1103,11 @@ func (p sessionPool) newSessionHandle(s session) (sh *sessionHandle) {`
`1103`	`1103`	`return sh`
`1104`	`1104`	`}`
`1105`	`1105`	`if p.TrackSessionHandles \|\| p.ActionOnInactiveTransaction == Warn \|\| p.ActionOnInactiveTransaction == WarnAndClose \|\| p.ActionOnInactiveTransaction == Close {`
`1106`		`- p.mu.Lock()`
`1107`		`- sh.trackedSessionHandle = p.trackedSessionHandles.PushBack(sh)`
`1108`	`1106`	`if p.TrackSessionHandles {`
`1109`	`1107`	`sh.stack = debug.Stack()`
`1110`	`1108`	`}`
	`1109`	`+ p.mu.Lock()`
	`1110`	`+ sh.trackedSessionHandle = p.trackedSessionHandles.PushBack(sh)`
`1111`	`1111`	`p.mu.Unlock()`
`1112`	`1112`	`}`
`1113`	`1113`	`return sh`