pgpool2.git / summary / log / commit / refs

commit    0535317dc16c0b46b104db166a1e02e55e410cfc
Author:   Tatsuo Ishii <ishii at sraoss.co.jp>
Date:     Thu May 05 02:39:14 2011 +0000

    Fix incorrect calculation of LSN in bytes.
    
    Change pg_last_xlog_receive_location() to
    pg_last_xlog_replay_location() because the latter respects actually
    replayed location which will give less chance for clients to have
    stale data in standby.
    
    Fix suggested by Anton Yuzhaninov.


 pool_worker_child.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/pool_worker_child.c b/pool_worker_child.c
index 612cedaee..014190e66 100644
--- a/pool_worker_child.c
+++ b/pool_worker_child.c
@@ -233,7 +233,7 @@ static void check_replication_time_lag(void)
 		}
 		else
 		{
-			query = "SELECT pg_last_xlog_receive_location()";
+			query = "SELECT pg_last_xlog_replay_location()";
 		}
 
 		sts = do_query(slots[i]->con, query, &res, PROTO_MAJOR_V3);
@@ -307,6 +307,12 @@ static void check_replication_time_lag(void)
  */
 static long text_to_lsn(char *text)
 {
+/*
+ * WAL segment size in bytes.  XXX We should fetch this from
+ * PostgreSQL, rather than having fixed value.
+ */
+#define WALSEGMENTSIZE 16 * 1024 * 1024
+
 	unsigned int xlogid;
 	unsigned int xrecoff;
 	unsigned long long int lsn;
@@ -316,7 +322,10 @@ static long text_to_lsn(char *text)
 		pool_error("text_to_lsn: wrong log location format: %s", text);
 		return 0;
 	}
-	lsn = xlogid * 16 * 1024 * 1024 * 255 + xrecoff;
+	lsn = xlogid * ((unsigned long long int)0xffffffff - WALSEGMENTSIZE) + xrecoff;
+#ifdef DEBUG
+	pool_log("lsn: %X %X %llX", xlogid, xrecoff, lsn);
+#endif
 	return lsn;
 }
 


[parent: a628fddfb845]