From 57b90552ebeedee61ffc99b3058ce18608c6fc4d Mon Sep 17 00:00:00 2001
From: Raven Black <ravenblack@dropbox.com>
Date: Fri, 10 May 2024 20:40:22 +0000
Subject: [PATCH] Comment explaining string-view by reference

Signed-off-by: Raven Black <ravenblack@dropbox.com>
---
 source/common/common/compiled_string_map.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/source/common/common/compiled_string_map.h b/source/common/common/compiled_string_map.h
index b8b0d64ce03d..bccb0d833ec0 100644
--- a/source/common/common/compiled_string_map.h
+++ b/source/common/common/compiled_string_map.h
@@ -49,6 +49,9 @@ namespace Envoy {
  * for the string node.
  */
 template <class Value> class CompiledStringMap {
+  // While it is usual to take a string_view by value, in this
+  // performance-critical context with repeatedly passing the same
+  // value, passing it by reference benchmarks out slightly faster.
   using FindFn = std::function<Value(const absl::string_view&)>;
 
 public: