Simplify main waiting loop of the archiver process

As coded, the timeout given to WaitLatch() was always equal to
PGARCH_AUTOWAKE_INTERVAL, as time() was called two times repeatedly.
This simplification could have been done in d75288f.

While on it, this adjusts a comment in pgarch.c to describe the archiver
in a more neutral way.

Author: Sravan Kumar, Nathan Bossart
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/CA+=NbjjqYE9-Lnw7H7DAiS5jebmoMikwZQb_sBP7kgBCn9q6Hg@mail.gmail.com

diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c
index 8ecdb9ca233c25afcdfccb233f84ab30840704b5..3c714a79c68129b8213a1a01275833a6ebfc406e 100644 (file)
--- a/src/backend/postmaster/pgarch.c
+++ b/src/backend/postmaster/pgarch.c
@@ -297,13 +297,12 @@ pgarch_waken_stop(SIGNAL_ARGS)
 static void
 pgarch_MainLoop(void)
 {
-       pg_time_t       last_copy_time = 0;
        bool            time_to_stop;
 
        /*
         * There shouldn't be anything for the archiver to do except to wait for a
-        * signal ... however, the archiver exists to protect our data, so she
-        * wakes up occasionally to allow herself to be proactive.
+        * signal ... however, the archiver exists to protect our data, so it
+        * wakes up occasionally to allow itself to be proactive.
         */
        do
        {
@@ -335,30 +334,21 @@ pgarch_MainLoop(void)
 
                /* Do what we're here for */
                pgarch_ArchiverCopyLoop();
-               last_copy_time = time(NULL);
 
                /*
                 * Sleep until a signal is received, or until a poll is forced by
-                * PGARCH_AUTOWAKE_INTERVAL having passed since last_copy_time, or
-                * until postmaster dies.
+                * PGARCH_AUTOWAKE_INTERVAL, or until postmaster dies.
                 */
                if (!time_to_stop)              /* Don't wait during last iteration */
                {
-                       pg_time_t       curtime = (pg_time_t) time(NULL);
-                       int                     timeout;
-
-                       timeout = PGARCH_AUTOWAKE_INTERVAL - (curtime - last_copy_time);
-                       if (timeout > 0)
-                       {
-                               int                     rc;
-
-                               rc = WaitLatch(MyLatch,
-                                                          WL_LATCH_SET | WL_TIMEOUT | WL_POSTMASTER_DEATH,
-                                                          timeout * 1000L,
-                                                          WAIT_EVENT_ARCHIVER_MAIN);
-                               if (rc & WL_POSTMASTER_DEATH)
-                                       time_to_stop = true;
-                       }
+                       int                     rc;
+
+                       rc = WaitLatch(MyLatch,
+                                                  WL_LATCH_SET | WL_TIMEOUT | WL_POSTMASTER_DEATH,
+                                                  PGARCH_AUTOWAKE_INTERVAL * 1000L,
+                                                  WAIT_EVENT_ARCHIVER_MAIN);
+                       if (rc & WL_POSTMASTER_DEATH)
+                               time_to_stop = true;
                }
 
                /*