Fix failure to rotate postmaster log file for size reasons on Windows.

When we eliminated "unnecessary" wakeups of the syslogger process, we
broke size-based logfile rotation on Windows, because on that platform
data transfer is done in a separate thread.  While non-Windows platforms
would recheck the output file size after every log message, Windows only
did so when the control thread woke up for some other reason, which might
be quite infrequent.  Per bug #7814 from Tsunezumi.  Back-patch to 9.2
where the problem was introduced.

Jeff Janes

diff --git a/src/backend/postmaster/syslogger.c b/src/backend/postmaster/syslogger.c
index 1c62bfe03a2058512f39ddee5f8ea6e8e909587d..534d69ec140516f31b9e275b18355f290149b9bc 100644 (file)
--- a/src/backend/postmaster/syslogger.c
+++ b/src/backend/postmaster/syslogger.c
@@ -1059,6 +1059,15 @@ pipeThread(void *arg)
                        bytes_in_logbuffer += bytesRead;
                        process_pipe_input(logbuffer, &bytes_in_logbuffer);
                }
+
+               /*
+                * If we've filled the current logfile, nudge the main thread to do a
+                * log rotation.
+                */
+               if (Log_RotationSize > 0 &&
+                       ftell(syslogFile) >= Log_RotationSize * 1024L)
+                       SetLatch(&sysLoggerLatch);
+
                LeaveCriticalSection(&sysloggerSection);
        }