Move default NBuffers setting into config.h, and rename it

to DEF_NBUFFERS for readability.  Make sure the default value is OK
according to postmaster.c's new sanity check for -B values.

src/backend/storage/buffer/buf_init.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.23 1999/05/25 16:10:56 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.24 1999/06/12 22:17:24 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -50,7 +50,7 @@ long	   *CurTraceBuf;
 #endif	 /* BMTRACE */
 int			ShowPinTrace = 0;
 
-int			NBuffers = NDBUFS;	/* NDBUFS defined in miscadmin.h */
+int			NBuffers = DEF_NBUFFERS;	/* default is set in config.h */
 int			Data_Descriptors;
 int			Free_List_Descriptor;
 int			Lookup_List_Descriptor;

src/include/config.h.in

@@ -21,6 +21,15 @@
  */
 #define MAXBACKENDS	(DEF_MAXBACKENDS > 1024 ? DEF_MAXBACKENDS : 1024)
 
+/*
+ * Default number of buffers in shared buffer pool (each of size BLCKSZ).
+ * This is just the default setting for the postmaster's -B switch.
+ * Perhaps it ought to be configurable from a configure switch.
+ * NOTE: default setting corresponds to the minimum number of buffers
+ * that postmaster.c will allow for the default MaxBackends value.
+ */
+#define DEF_NBUFFERS (DEF_MAXBACKENDS > 8 ? DEF_MAXBACKENDS * 2 : 16)
+
 /*
  * Size of a disk block --- currently, this limits the size of a tuple.
  * You can set it bigger if you need bigger tuples.

src/include/miscadmin.h

@@ -11,7 +11,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: miscadmin.h,v 1.39 1999/05/25 16:13:23 momjian Exp $
+ * $Id: miscadmin.h,v 1.40 1999/06/12 22:17:23 tgl Exp $
  *
  * NOTES
  *	  some of the information in this file will be moved to
@@ -102,12 +102,6 @@ extern Oid	LastOidProcessed;	/* for query rewrite */
 /* #define MAX_QUERY_SIZE	 (BLCKSZ*2) */
 #define MAX_PARSE_BUFFER MAX_QUERY_SIZE
 
-/*
- *		default number of buffers in buffer pool
- *
- */
-#define NDBUFS 64
-
 /*****************************************************************************
  *	  pdir.h --																 *
  *			POSTGRES directory path definitions.							 *