diff --git a/guix-data-service/web/server.scm b/guix-data-service/web/server.scm
index 2661b44..2ae9b69 100644
--- a/guix-data-service/web/server.scm
+++ b/guix-data-service/web/server.scm
@@ -206,7 +206,7 @@ port. Also, the port used can be changed by passing the --port option.\n"
                        #:destructor
                        (lambda (conn)
                          (close-postgresql-connection conn "web"))
-                       #:default-max-waiters 300
+                       #:default-max-waiters (floor (/ postgresql-connections 2))
                        #:default-checkout-timeout (/ postgresql-statement-timeout
                                                      1000)
                        #:scheduler priority-scheduler))