parallel restore fixes - Mailing list pgsql-hackers

The attached patch fixes two issues with parallel restore:

    * the static buffer problem in dumputils.c::fmtId() on Windows
      (solution: use thread-local storage)
    * ReopenPtr() is called too often


There is one remaining bug I know of that I can reproduce: we can get
into deadlock when two tables are foreign keyed to each other. So I need
to get a bit more paranoid about dependencies.

I can't reproduce Olivier Prennant's file closing problem on Unixware.
Is it still happening after application of this patch?

cheers

andrew
Index: src/bin/pg_dump/dumputils.c
===================================================================
RCS file: /home/cvsmirror/pg/pgsql/src/bin/pg_dump/dumputils.c,v
retrieving revision 1.44
diff -c -r1.44 dumputils.c
*** src/bin/pg_dump/dumputils.c    22 Jan 2009 20:16:07 -0000    1.44
--- src/bin/pg_dump/dumputils.c    9 Mar 2009 22:33:32 -0000
***************
*** 31,36 ****
--- 31,50 ----
  static void AddAcl(PQExpBuffer aclbuf, const char *keyword,
                     const char *subname);

+ #ifdef WIN32
+ static DWORD tls_index;
+ #endif
+
+ void
+ init_dump_utils()
+ {
+ #ifdef WIN32
+     /* reserve one thread-local slot for the fmtId query buffer address */
+     tls_index = TlsAlloc();
+ #endif
+ }
+
+

  /*
   *    Quotes input string if it's not a legitimate SQL identifier as-is.
***************
*** 42,55 ****
--- 56,87 ----
  const char *
  fmtId(const char *rawid)
  {
+ #ifdef WIN32
+     PQExpBuffer id_return;
+ #else
      static PQExpBuffer id_return = NULL;
+ #endif
      const char *cp;
      bool        need_quotes = false;
+     char *retval;
+
+ #ifdef WIN32
+     id_return = (PQExpBuffer) TlsGetValue(tls_index); /* returns 0 until set */
+ #endif

      if (id_return)                /* first time through? */
+     {
+         /* same buffer, just wipe contents */
          resetPQExpBuffer(id_return);
+     }
      else
+     {
+         /* new buffer */
          id_return = createPQExpBuffer();
+ #ifdef WIN32
+         TlsSetValue(tls_index,id_return);
+ #endif
+     }

      /*
       * These checks need to match the identifier production in scan.l. Don't
***************
*** 111,117 ****
          appendPQExpBufferChar(id_return, '\"');
      }

!     return id_return->data;
  }


--- 143,151 ----
          appendPQExpBufferChar(id_return, '\"');
      }

!     retval = id_return->data;
!     return retval;
!
  }


Index: src/bin/pg_dump/dumputils.h
===================================================================
RCS file: /home/cvsmirror/pg/pgsql/src/bin/pg_dump/dumputils.h,v
retrieving revision 1.23
diff -c -r1.23 dumputils.h
*** src/bin/pg_dump/dumputils.h    22 Jan 2009 20:16:07 -0000    1.23
--- src/bin/pg_dump/dumputils.h    9 Mar 2009 22:33:32 -0000
***************
*** 19,24 ****
--- 19,25 ----
  #include "libpq-fe.h"
  #include "pqexpbuffer.h"

+ extern void init_dump_utils(void);
  extern const char *fmtId(const char *identifier);
  extern void appendStringLiteral(PQExpBuffer buf, const char *str,
                      int encoding, bool std_strings);
Index: src/bin/pg_dump/pg_backup_archiver.c
===================================================================
RCS file: /home/cvsmirror/pg/pgsql/src/bin/pg_dump/pg_backup_archiver.c,v
retrieving revision 1.165
diff -c -r1.165 pg_backup_archiver.c
*** src/bin/pg_dump/pg_backup_archiver.c    5 Mar 2009 14:51:10 -0000    1.165
--- src/bin/pg_dump/pg_backup_archiver.c    9 Mar 2009 22:33:32 -0000
***************
*** 3467,3478 ****

      /*
       * Close and reopen the input file so we have a private file pointer
!      * that doesn't stomp on anyone else's file pointer.
       *
!      * Note: on Windows, since we are using threads not processes, this
!      * *doesn't* close the original file pointer but just open a new one.
       */
!     (AH->ReopenPtr) (AH);

      /*
       * We need our own database connection, too
--- 3467,3486 ----

      /*
       * Close and reopen the input file so we have a private file pointer
!      * that doesn't stomp on anyone else's file pointer, if we're actually
!      * going to need to read from the file. Otherwise, just close it
!      * except on Windows, where it will possibly be needed by other threads.
       *
!      * Note: on Windows, since we are using threads not processes, the
!      * reopen call *doesn't* close the original file pointer but just open
!      * a new one.
       */
!     if (te->section == SECTION_DATA )
!         (AH->ReopenPtr) (AH);
! #ifndef WIN32
!     else
!         (AH->ClosePtr) (AH);
! #endif;

      /*
       * We need our own database connection, too
***************
*** 3490,3495 ****
--- 3498,3505 ----
      PQfinish(AH->connection);
      AH->connection = NULL;

+     /* If we reopened the file, we are done with it, so close it now */
+     if (te->section == SECTION_DATA )
      (AH->ClosePtr) (AH);

      if (retval == 0 && AH->public.n_errors)
Index: src/bin/pg_dump/pg_dump.c
===================================================================
RCS file: /home/cvsmirror/pg/pgsql/src/bin/pg_dump/pg_dump.c,v
retrieving revision 1.528
diff -c -r1.528 pg_dump.c
*** src/bin/pg_dump/pg_dump.c    4 Mar 2009 11:57:00 -0000    1.528
--- src/bin/pg_dump/pg_dump.c    9 Mar 2009 22:33:32 -0000
***************
*** 287,292 ****
--- 287,294 ----

      set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_dump"));

+     init_dump_utils();
+
      g_verbose = false;

      strcpy(g_comment_start, "-- ");
Index: src/bin/pg_dump/pg_dumpall.c
===================================================================
RCS file: /home/cvsmirror/pg/pgsql/src/bin/pg_dump/pg_dumpall.c,v
retrieving revision 1.119
diff -c -r1.119 pg_dumpall.c
*** src/bin/pg_dump/pg_dumpall.c    4 Mar 2009 11:57:00 -0000    1.119
--- src/bin/pg_dump/pg_dumpall.c    9 Mar 2009 22:33:32 -0000
***************
*** 136,141 ****
--- 136,143 ----

      set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_dump"));

+     init_dump_utils();
+
      progname = get_progname(argv[0]);

      if (argc > 1)
Index: src/bin/pg_dump/pg_restore.c
===================================================================
RCS file: /home/cvsmirror/pg/pgsql/src/bin/pg_dump/pg_restore.c,v
retrieving revision 1.94
diff -c -r1.94 pg_restore.c
*** src/bin/pg_dump/pg_restore.c    26 Feb 2009 16:02:38 -0000    1.94
--- src/bin/pg_dump/pg_restore.c    9 Mar 2009 22:33:32 -0000
***************
*** 40,45 ****
--- 40,46 ----
   */

  #include "pg_backup_archiver.h"
+ #include "dumputils.h"

  #include <ctype.h>

***************
*** 125,130 ****
--- 126,133 ----

      set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_dump"));

+     init_dump_utils();
+
      opts = NewRestoreOptions();

      progname = get_progname(argv[0]);