From: Vinay Sajip <vinay_sajip@yahoo.co.uk>
Date: Mon, 29 Aug 2022 21:29:22 +0000 (+0100)
Subject: gh-91305: Add a note about DatagramHandler and DNS latency. (GH-96380)
X-Git-Tag: v3.12.0a1~530
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=6324b135acb92042017c2364540c37426b0ea65f;p=thirdparty%2FPython%2Fcpython.git

gh-91305: Add a note about DatagramHandler and DNS latency. (GH-96380)
---

diff --git a/Doc/library/logging.handlers.rst b/Doc/library/logging.handlers.rst
index f125dfe64a03..a0129279f4db 100644
--- a/Doc/library/logging.handlers.rst
+++ b/Doc/library/logging.handlers.rst
@@ -572,6 +572,13 @@ over UDP sockets.
    Returns a new instance of the :class:`DatagramHandler` class intended to
    communicate with a remote machine whose address is given by *host* and *port*.
 
+   .. note:: As UDP is not a streaming protocol, there is no persistent connection
+      between an instance of this handler and *host*. For this reason, when using a
+      network socket, a DNS lookup might have to be made each time an event is
+      logged, which can introduce some latency into the system. If this affects you,
+      you can do a lookup yourself and initialize this handler using the looked-up IP
+      address rather than the hostname.
+
    .. versionchanged:: 3.4
       If ``port`` is specified as ``None``, a Unix domain socket is created
       using the value in ``host`` - otherwise, a UDP socket is created.