fixup! fixup! fixup! fixup! fixup! Fixes #19675: Restart HTTP clients…

… when configuration changes

Fixes #19675: Restart HTTP clients when configuration changes

relay/sources/relayd/src/lib.rs

@@ -342,6 +342,8 @@ impl JobConfig {
         //   will continue normally with previous configuration in the old client.
         // * when all requests in the old client are over, all references to the `Arc` will disappear
         //   and the old client itself will be dropped.
+        // * the unchanged downstream clients will be kept thanks to the reference to the old client
+        //   added to the new `HashMap`.
         //
         // To enable this replacement, we store the clients in a `RwLock`. Write locking will be
         // possible as when using the clients to make requests, we don't lock for the request
@@ -400,6 +402,7 @@ impl JobConfig {
             // this will drop the previous `HashMap` and free the references to the clients that it
             // contained. The only references left are clients with ongoing requests, which will all be
             // dropped when they are over.
+            // It would also be possible to modify the current `HashMap in place` for slightly better performance.
             *downstream_clients = new_downstream_clients;
         }