On 28/08/2023 18:55, Jeff Janes wrote:
Since this commit, I'm getting a lot (63 per restart) of messages:
LOG: could not close client or listen socket: Bad file descriptor
All I have to do to get the message is turn logging_collector = on and
restart.
The close failure condition existed before the commit, it just wasn't
logged before. So, did the extra logging added here just uncover a
pre-existing bug?
Yes, so it seems. Syslogger is started before the ListenSockets array is
initialized, so its still all zeros. When syslogger is forked, the child
process tries to close all the listen sockets, which are all zeros. So
syslogger calls close(0) MAXLISTEN (64) times. Attached patch moves the
array initialization earlier.
The first close(0) actually does have an effect: it closes stdin, which
is fd 0. That is surely accidental, but I wonder if we should indeed
close stdin in child processes? The postmaster process doesn't do
anything with stdin either, although I guess a library might try to read
a passphrase from stdin before starting up, for example.
--
Heikki Linnakangas
Neon (https://neon.tech)
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 41bccb46a87..6b9e10bffa0 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -596,6 +596,9 @@ PostmasterMain(int argc, char *argv[])
IsPostmasterEnvironment = true;
+ for (i = 0; i < MAXLISTEN; i++)
+ ListenSocket[i] = PGINVALID_SOCKET;
+
/*
* Start our win32 signal implementation
*/
@@ -1176,12 +1179,9 @@ PostmasterMain(int argc, char *argv[])
/*
* Establish input sockets.
*
- * First, mark them all closed, and set up an on_proc_exit function that's
- * charged with closing the sockets again at postmaster shutdown.
+ * Set up an on_proc_exit function that's charged with closing the sockets
+ * again at postmaster shutdown.
*/
- for (i = 0; i < MAXLISTEN; i++)
- ListenSocket[i] = PGINVALID_SOCKET;
-
on_proc_exit(CloseServerPorts, 0);
if (ListenAddresses)
