lib: adding perf notes js_stream_socket.js

ryanj · MylesBorins · commit 7d0631aefcbe · 2019-12-17T17:06:54.000-05:00
Leaving var in place of let for performance optimization in short loops in hot paths. Added comments explaining why. PR-URL: #30415 Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com> Reviewed-By: Denys Otrishko <shishugi@gmail.com> Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
diff --git a/lib/internal/js_stream_socket.js b/lib/internal/js_stream_socket.js
@@ -157,6 +157,7 @@ class JSStreamSocket extends Socket {
     let pending = bufs.length;
 
     this.stream.cork();
+    // Use `var` over `let` for performance optimization.
     for (var i = 0; i < bufs.length; ++i)
       this.stream.write(bufs[i], done);
     this.stream.uncork();
