From: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Date: Sat, 13 Feb 2021 22:42:00 +0000 (+0100)
Subject: Awake the pool client outside the critical section
X-Git-Tag: 3.0.dev0~87^2~75
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=24cbbe5472d9d68de4ae8fd3a3849134804ab9a8;p=thirdparty%2Fpsycopg.git

Awake the pool client outside the critical section
---

diff --git a/psycopg3/psycopg3/pool.py b/psycopg3/psycopg3/pool.py
index 358203ec5..b4a9eaf17 100644
--- a/psycopg3/psycopg3/pool.py
+++ b/psycopg3/psycopg3/pool.py
@@ -148,14 +148,18 @@ class ConnectionPool:
         # Critical section: if there is a client waiting give it the connection
         # otherwise put it back into the pool.
         with self._lock:
+            pos: Optional[WaitingClient] = None
             if self._waiting:
-                # Give the connection to the client and notify it
+                # Extract the first client from the queue
                 pos = self._waiting.popleft()
-                pos.set(conn)
             else:
-                # No client waiting for a connection: put it back into the queue
+                # No client waiting for a connection: put it back into the pool
                 self._pool.append(conn)
 
+        # If we found a client in queue, give it the connection and notify it
+        if pos:
+            pos.set(conn)
+
     def _reset_transaction_status(self, conn: Connection) -> None:
         """
         Bring a connection to IDLE state or close it.