Implement NOWAIT option for BASE_BACKUP command

Specifying this option makes the server not wait for the
xlog to be archived, or emit a warning that it can't,
instead leaving the responsibility with the client.

This is useful when the log is being streamed using
the streaming protocol in parallel with the backup,
without having log archiving enabled.

diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml
index b93c268167d5da7a9edd7a45dc57a7183ab054d3..c09d961d67e22748b5807313aecf6d63d071b3a2 100644 (file)
--- a/doc/src/sgml/protocol.sgml
+++ b/doc/src/sgml/protocol.sgml
@@ -1473,7 +1473,7 @@ The commands accepted in walsender mode are:
   
 
   
-    BASE_BACKUP [LABEL 'label'] [PROGRESS] [FAST] [WAL]
+    BASE_BACKUP [LABEL 'label'] [PROGRESS] [FAST] [WAL] [NOWAIT]
     
      
       Instructs the server to start streaming a base backup.
@@ -1530,6 +1530,19 @@ The commands accepted in walsender mode are:
          
         
        
+
+       
+        NOWAIT
+        
+         
+          By default, the backup will wait until the last required xlog
+          segment has been archived, or emit a warning if log archiving is
+          not enabled. Specifying NOWAIT disables both
+          the waiting and the warning, leaving the client responsible for
+          ensuring the required log is available.
+         
+         
+       
       
      
      

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 72a1a158c075395b3685bc089c05b7550029ad7f..8e9dc7ba92a954345953971a0eee1cc87d584765 100644 (file)
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -8865,7 +8865,7 @@ pg_stop_backup(PG_FUNCTION_ARGS)
    XLogRecPtr  stoppoint;
    char        stopxlogstr[MAXFNAMELEN];
 
-   stoppoint = do_pg_stop_backup(NULL);
+   stoppoint = do_pg_stop_backup(NULL, true);
 
    snprintf(stopxlogstr, sizeof(stopxlogstr), "%X/%X",
             stoppoint.xlogid, stoppoint.xrecoff);
@@ -8880,7 +8880,7 @@ pg_stop_backup(PG_FUNCTION_ARGS)
  * the non-exclusive backup specified by 'labelfile'.
  */
 XLogRecPtr
-do_pg_stop_backup(char *labelfile)
+do_pg_stop_backup(char *labelfile, bool waitforarchive)
 {
    bool        exclusive = (labelfile == NULL);
    XLogRecPtr  startpoint;
@@ -9079,7 +9079,7 @@ do_pg_stop_backup(char *labelfile)
     * wish to wait, you can set statement_timeout.  Also, some notices are
     * issued to clue in anyone who might be doing this interactively.
     */
-   if (XLogArchivingActive())
+   if (waitforarchive && XLogArchivingActive())
    {
        XLByteToPrevSeg(stoppoint, _logId, _logSeg);
        XLogFileName(lastxlogfilename, ThisTimeLineID, _logId, _logSeg);
@@ -9120,7 +9120,7 @@ do_pg_stop_backup(char *labelfile)
        ereport(NOTICE,
                (errmsg("pg_stop_backup complete, all required WAL segments have been archived")));
    }
-   else
+   else if (waitforarchive)
        ereport(NOTICE,
                (errmsg("WAL archiving is not enabled; you must ensure that all required WAL segments are copied through other means to complete the backup")));
 

diff --git a/src/backend/replication/basebackup.c b/src/backend/replication/basebackup.c
index d94b61f23ef57ea1d0e9481e592fc38d553a7b7b..db4cc640e48cefbd579efde19a0a0d3e6682779b 100644 (file)
--- a/src/backend/replication/basebackup.c
+++ b/src/backend/replication/basebackup.c
@@ -37,6 +37,7 @@ typedef struct
    const char *label;
    bool        progress;
    bool        fastcheckpoint;
+   bool        nowait;
    bool        includewal;
 }  basebackup_options;
 
@@ -173,7 +174,7 @@ perform_base_backup(basebackup_options *opt, DIR *tblspcdir)
    }
    PG_END_ENSURE_ERROR_CLEANUP(base_backup_cleanup, (Datum) 0);
 
-   endptr = do_pg_stop_backup(labelfile);
+   endptr = do_pg_stop_backup(labelfile, !opt->nowait);
 
    if (opt->includewal)
    {
@@ -260,6 +261,7 @@ parse_basebackup_options(List *options, basebackup_options *opt)
    bool        o_label = false;
    bool        o_progress = false;
    bool        o_fast = false;
+   bool        o_nowait = false;
    bool        o_wal = false;
 
    MemSet(opt, 0, sizeof(*opt));
@@ -294,6 +296,15 @@ parse_basebackup_options(List *options, basebackup_options *opt)
            opt->fastcheckpoint = true;
            o_fast = true;
        }
+       else if (strcmp(defel->defname, "nowait") == 0)
+       {
+           if (o_nowait)
+               ereport(ERROR,
+                       (errcode(ERRCODE_SYNTAX_ERROR),
+                        errmsg("duplicate option \"%s\"", defel->defname)));
+           opt->nowait = true;
+           o_nowait = true;
+       }
        else if (strcmp(defel->defname, "wal") == 0)
        {
            if (o_wal)

diff --git a/src/backend/replication/repl_gram.y b/src/backend/replication/repl_gram.y
index e1a4a51a0e9696c43d19a699e9a68ae3afcc856b..4930ad1d097c6e8ddfee8b117cdf95c47a5505da 100644 (file)
--- a/src/backend/replication/repl_gram.y
+++ b/src/backend/replication/repl_gram.y
@@ -71,6 +71,7 @@ Node *replication_parse_result;
 %token K_LABEL
 %token K_PROGRESS
 %token K_FAST
+%token K_NOWAIT
 %token K_WAL
 %token K_START_REPLICATION
 
@@ -107,7 +108,7 @@ identify_system:
            ;
 
 /*
- * BASE_BACKUP [LABEL ''] [PROGRESS] [FAST] [WAL]
+ * BASE_BACKUP [LABEL ''] [PROGRESS] [FAST] [WAL] [NOWAIT]
  */
 base_backup:
            K_BASE_BACKUP base_backup_opt_list
@@ -142,6 +143,11 @@ base_backup_opt:
                  $$ = makeDefElem("wal",
                           (Node *)makeInteger(TRUE));
                }
+           | K_NOWAIT
+               {
+                 $$ = makeDefElem("nowait",
+                          (Node *)makeInteger(TRUE));
+               }
            ;
 
 /*

diff --git a/src/backend/replication/repl_scanner.l b/src/backend/replication/repl_scanner.l
index 87e77d975a904842c1dcbf97cd50531825ab8df6..f5b260119ec28b822e06c0231e7a2423eb4d14b1 100644 (file)
--- a/src/backend/replication/repl_scanner.l
+++ b/src/backend/replication/repl_scanner.l
@@ -60,6 +60,7 @@ BASE_BACKUP           { return K_BASE_BACKUP; }
 FAST           { return K_FAST; }
 IDENTIFY_SYSTEM        { return K_IDENTIFY_SYSTEM; }
 LABEL          { return K_LABEL; }
+NOWAIT         { return K_NOWAIT; }
 PROGRESS           { return K_PROGRESS; }
 WAL            { return K_WAL; }
 START_REPLICATION  { return K_START_REPLICATION; }

diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h
index e7adead9a2842466adc5747e9f781aade0bf436c..ff73272f755dd505bc119fb74e6474cb119767a6 100644 (file)
--- a/src/include/access/xlog.h
+++ b/src/include/access/xlog.h
@@ -318,7 +318,7 @@ extern void WakeupRecovery(void);
  * Starting/stopping a base backup
  */
 extern XLogRecPtr do_pg_start_backup(const char *backupidstr, bool fast, char **labelfile);
-extern XLogRecPtr do_pg_stop_backup(char *labelfile);
+extern XLogRecPtr do_pg_stop_backup(char *labelfile, bool waitforarchive);
 extern void do_pg_abort_backup(void);
 
 /* File path names (all relative to $PGDATA) */