Assorted corrections to the patch to add WAL receiver replies.

Per reports from Fujii Masao.

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index b6f8621278c96399949f9399ddeca895c7a75e62..9505caf47a269d7fa66b910c6205f83b09394e0c 100644 (file)
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -1984,29 +1984,6 @@ SET ENABLE_SEQSCAN TO OFF;
        </listitem>
       </varlistentry>
 
-      <varlistentry id="guc-wal-receiver-status-interval" xreflabel="wal_receiver_status_interval">
-       <term><varname>wal_receiver_status_interval</varname> (<type>integer</type>)</term>
-       <indexterm>
-        <primary><varname>wal_receiver_status_interval</> configuration parameter</primary>
-       </indexterm>
-       <listitem>
-       <para>
-        Specifies the minimum frequency, in seconds, for the WAL receiver
-        process on the standby to send information about replication progress
-        to the primary, where they can be seen using the
-        <literal>pg_stat_replication</literal> view.  The standby will report
-        the last transaction log position it has written, the last position it
-        has flushed to disk, and the last position it has applied.  Updates are
-        sent each time the write or flush positions changed, or at least as
-        often as specified by this parameter.  Thus, the apply position may
-        lag slightly behind the true position.  Setting this parameter to zero
-        disables status updates completely.  This parameter can only be set in
-        the <filename>postgresql.conf</> file or on the server command line.
-        The default value is 10 seconds.
-       </para>
-       </listitem>
-      </varlistentry>
-
      <varlistentry id="guc-vacuum-defer-cleanup-age" xreflabel="vacuum_defer_cleanup_age">
       <term><varname>vacuum_defer_cleanup_age</varname> (<type>integer</type>)</term>
       <indexterm>
@@ -2121,6 +2098,29 @@ SET ENABLE_SEQSCAN TO OFF;
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-wal-receiver-status-interval" xreflabel="wal_receiver_status_interval">
+      <term><varname>wal_receiver_status_interval</varname> (<type>integer</type>)</term>
+      <indexterm>
+       <primary><varname>wal_receiver_status_interval</> configuration parameter</primary>
+      </indexterm>
+      <listitem>
+      <para>
+       Specifies the minimum frequency, in seconds, for the WAL receiver
+       process on the standby to send information about replication progress
+       to the primary, where they can be seen using the
+       <literal>pg_stat_replication</literal> view.  The standby will report
+       the last transaction log position it has written, the last position it
+       has flushed to disk, and the last position it has applied.  Updates are
+       sent each time the write or flush positions changed, or at least as
+       often as specified by this parameter.  Thus, the apply position may
+       lag slightly behind the true position.  Setting this parameter to zero
+       disables status updates completely.  This parameter can only be set in
+       the <filename>postgresql.conf</> file or on the server command line.
+       The default value is 10 seconds.
+      </para>
+      </listitem>
+     </varlistentry>
+
      </variablelist>
     </sect2>
    </sect1>

diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index 3ad95b495ec8dbe86d218959d8336b8576847d24..fe9961638c6fe4bcb2cc0f9b67b6e77633319dcc 100644 (file)
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -89,6 +89,11 @@ static uint32 sendOff = 0;
  */
 static XLogRecPtr sentPtr = {0, 0};
 
+/*
+ * Buffer for processing reply messages.
+ */
+static StringInfoData reply_message;
+
 /* Flags set by signal handlers for later service in main loop */
 static volatile sig_atomic_t got_SIGHUP = false;
 volatile sig_atomic_t walsender_shutdown_requested = false;
@@ -469,7 +474,7 @@ ProcessRepliesIfAny(void)
        switch (firstchar)
        {
                        /*
-                        * 'd' means a standby reply wrapped in a COPY BOTH packet.
+                        * 'd' means a standby reply wrapped in a CopyData packet.
                         */
                case 'd':
                        ProcessStandbyReplyMessage();
@@ -495,16 +500,15 @@ ProcessRepliesIfAny(void)
 static void
 ProcessStandbyReplyMessage(void)
 {
-       static StringInfoData input_message;
        StandbyReplyMessage     reply;
        char msgtype;
 
-       initStringInfo(&input_message);
+       resetStringInfo(&reply_message);
 
        /*
         * Read the message contents.
         */
-       if (pq_getmessage(&input_message, 0))
+       if (pq_getmessage(&reply_message, 0))
        {
                ereport(COMMERROR,
                                (errcode(ERRCODE_PROTOCOL_VIOLATION),
@@ -516,13 +520,16 @@ ProcessStandbyReplyMessage(void)
         * Check message type from the first byte. At the moment, there is only
         * one type.
         */
-       msgtype = pq_getmsgbyte(&input_message);
+       msgtype = pq_getmsgbyte(&reply_message);
        if (msgtype != 'r')
+       {
                ereport(COMMERROR,
                                (errcode(ERRCODE_PROTOCOL_VIOLATION),
                                 errmsg("unexpected message type %c", msgtype)));
+               proc_exit(0);
+       }
 
-       pq_copymsgbytes(&input_message, (char *) &reply, sizeof(StandbyReplyMessage));
+       pq_copymsgbytes(&reply_message, (char *) &reply, sizeof(StandbyReplyMessage));
 
        elog(DEBUG2, "write %X/%X flush %X/%X apply %X/%X ",
                 reply.write.xlogid, reply.write.xrecoff,
@@ -559,6 +566,12 @@ WalSndLoop(void)
         */
        output_message = palloc(1 + sizeof(WalDataMessageHeader) + MAX_SEND_SIZE);
 
+       /*
+        * Allocate buffer that will be used for processing reply messages.  As
+        * above, do this just once to reduce palloc overhead.
+        */
+       initStringInfo(&reply_message);
+
        /* Loop forever, unless we get an error */
        for (;;)
        {