Allow internal sorts to be stored in memory rather than in files.

src/backend/executor/nodeMergejoin.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *    $Header: /cvsroot/pgsql/src/backend/executor/nodeMergejoin.c,v 1.5 1996/11/10 02:59:54 momjian Exp $
+ *    $Header: /cvsroot/pgsql/src/backend/executor/nodeMergejoin.c,v 1.6 1997/08/06 03:41:29 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -374,6 +374,18 @@ ExecMergeTupleDump(ExprContext *econtext, MergeJoinState *mergestate)
     printf("******** \n");
 }
  
+static void
+CleanUpSort(Plan *plan) {
+
+    if (plan == NULL)
+	return;
+    
+    if (plan->type == T_Sort) {
+	Sort *sort = (Sort *)plan;
+	psort_end(sort);
+    }
+}
+
 /* ----------------------------------------------------------------
  *   	ExecMergeJoin
  *
@@ -676,6 +688,8 @@ ExecMergeJoin(MergeJoin *node)
 	     */
             if (TupIsNull(outerTupleSlot)) {
 		MJ_printf("ExecMergeJoin: **** outer tuple is nil ****\n");
+		CleanUpSort(node->join.lefttree->lefttree);
+		CleanUpSort(node->join.righttree->lefttree);
 		return NULL;
 	    }
 	    

src/backend/tcop/postgres.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *    $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.36 1997/07/29 16:14:40 thomas Exp $
+ *    $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.37 1997/08/06 03:41:41 momjian Exp $
  *
  * NOTES
  *    this is the "main" module of the postgres backend and
@@ -108,6 +108,7 @@ extern int      lockingOff;
 extern int      NBuffers;
 
 int     fsyncOff = 0;
+int	SortMem = 512;
 
 int     dontExecute = 0;
 static int      ShowStats;
@@ -1039,6 +1040,15 @@ PostgresMain(int argc, char *argv[])
             flagQ = 1;
             break;
 
+        case 'S':
+            /* ----------------
+             *  S - amount of sort memory to use in 1k bytes
+             * ----------------
+             */
+            SortMem = atoi(optarg);
+            break;
+
+#ifdef NOT_USED
         case 'S':
             /* ----------------
              *  S - assume stable main memory
@@ -1048,6 +1058,7 @@ PostgresMain(int argc, char *argv[])
             flagS = 1;
             SetTransactionFlushEnabled(false);
             break;
+#endif
             
         case 's':
             /* ----------------
@@ -1173,6 +1184,7 @@ PostgresMain(int argc, char *argv[])
         printf("\ttimings   =    %c\n", ShowStats ? 't' : 'f');
         printf("\tdates     =    %s\n", EuroDates ? "European" : "Normal");
         printf("\tbufsize   =    %d\n", NBuffers);
+        printf("\tsortmem   =    %d\n", SortMem);
         
         printf("\tquery echo =   %c\n", EchoQuery ? 't' : 'f');
         printf("\tmultiplexed backend? =  %c\n", multiplexedBackend ? 't' : 'f');
@@ -1280,7 +1292,7 @@ PostgresMain(int argc, char *argv[])
      */
     if (IsUnderPostmaster == false) {
         puts("\nPOSTGRES backend interactive interface");
-        puts("$Revision: 1.36 $ $Date: 1997/07/29 16:14:40 $");
+        puts("$Revision: 1.37 $ $Date: 1997/08/06 03:41:41 $");
     }
     
     /* ----------------

src/backend/utils/sort/lselect.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *    $Header: /cvsroot/pgsql/src/backend/utils/sort/Attic/lselect.c,v 1.3 1997/05/20 11:35:48 vadim Exp $
+ *    $Header: /cvsroot/pgsql/src/backend/utils/sort/Attic/lselect.c,v 1.4 1997/08/06 03:41:47 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -26,37 +26,14 @@
 #include "utils/psort.h"
 #include "utils/lselect.h"
 
-extern	Relation	SortRdesc;		/* later static */ 
-
-/*
- *	PUTTUP		- writes the next tuple
- *	ENDRUN		- mark end of run
- *	GETLEN		- reads the length of the next tuple
- *	ALLOCTUP	- returns space for the new tuple
- *	SETTUPLEN	- stores the length into the tuple
- *	GETTUP		- reads the tuple
- *
- *	Note:
- *		LEN field must be a short; FP is a stream
- */
-
 #define	PUTTUP(TUP, FP)	fwrite((char *)TUP, (TUP)->t_len, 1, FP)
-#define	ENDRUN(FP)	fwrite((char *)&shortzero, sizeof (shortzero), 1, FP)
-#define	GETLEN(LEN, FP)	fread(&(LEN), sizeof (shortzero), 1, FP)
-#define	ALLOCTUP(LEN)	((HeapTuple)palloc((unsigned)LEN))
-#define	GETTUP(TUP, LEN, FP)\
-	fread((char *)(TUP) + sizeof (shortzero), 1, (LEN) - sizeof (shortzero), FP)
-#define	SETTUPLEN(TUP, LEN)	(TUP)->t_len = LEN
 
 /*
  *	USEMEM		- record use of memory
  *	FREEMEM		- record freeing of memory
- *	FULLMEM		- 1 iff a tuple will fit
  */
-
-#define	USEMEM(AMT)	SortMemory -= (AMT)
-#define	FREEMEM(AMT)	SortMemory += (AMT)
-#define	LACKMEM()	(SortMemory <= BLCKSZ)		/* not accurate */
+#define	USEMEM(context,AMT)	context->sortMem -= (AMT)
+#define	FREEMEM(context,AMT)	context->sortMem += (AMT)
 
 /*
  *	lmerge		- merges two leftist trees into one
@@ -67,12 +44,12 @@ extern	Relation	SortRdesc;		/* later static */
  *		speed up code significantly.
  */
 struct leftist *
-lmerge(struct leftist *pt, struct leftist *qt)
+lmerge(struct leftist *pt, struct leftist *qt, LeftistContext context)
 {
     register struct	leftist	*root, *majorLeftist, *minorLeftist;
     int		dist;
     
-    if (tuplecmp(pt->lt_tuple, qt->lt_tuple)) {
+    if (tuplecmp(pt->lt_tuple, qt->lt_tuple, context)) {
 	root = pt;
 	majorLeftist = qt;
     } else {
@@ -83,7 +60,7 @@ lmerge(struct leftist *pt, struct leftist *qt)
 	root->lt_left = majorLeftist;
     else {
 	if ((minorLeftist = root->lt_right) != NULL)
-	    majorLeftist = lmerge(majorLeftist, minorLeftist);
+	    majorLeftist = lmerge(majorLeftist, minorLeftist, context);
 	if ((dist = root->lt_left->lt_dist) < majorLeftist->lt_dist) {
 	    root->lt_dist = 1 + dist;
 	    root->lt_right = root->lt_left;
@@ -97,11 +74,11 @@ lmerge(struct leftist *pt, struct leftist *qt)
 }
 
 static struct leftist *
-linsert(struct leftist *root, struct leftist *new1)
+linsert(struct leftist *root, struct leftist *new1, LeftistContext context)
 {
     register struct	leftist	*left, *right;
     
-    if (! tuplecmp(root->lt_tuple, new1->lt_tuple)) {
+    if (! tuplecmp(root->lt_tuple, new1->lt_tuple, context)) {
 	new1->lt_left = root;
 	return(new1);
     }
@@ -116,7 +93,7 @@ linsert(struct leftist *root, struct leftist *new1)
 	}
 	return(root);
     }
-    right = linsert(right, new1);
+    right = linsert(right, new1, context);
     if (right->lt_dist < left->lt_dist) {
 	root->lt_dist = 1 + left->lt_dist;
 	root->lt_left = right;
@@ -142,7 +119,8 @@ linsert(struct leftist *root, struct leftist *new1)
  */
 HeapTuple
 gettuple(struct leftist **treep,
-	 short *devnum)		/* device from which tuple came */
+	 short *devnum,		/* device from which tuple came */
+	 LeftistContext context)
 {
     register struct	leftist	 *tp;
     HeapTuple	tup;
@@ -153,9 +131,9 @@ gettuple(struct leftist **treep,
     if (tp->lt_dist == 1)				/* lt_left == NULL */
 	*treep = tp->lt_left;
     else
-	*treep = lmerge(tp->lt_left, tp->lt_right);
+	*treep = lmerge(tp->lt_left, tp->lt_right, context);
     
-    FREEMEM(sizeof (struct leftist));
+    FREEMEM(context,sizeof (struct leftist));
     FREE(tp);
     return(tup);
 }
@@ -169,14 +147,17 @@ gettuple(struct leftist **treep,
  *	Note:
  *		Currently never returns NULL BUG
  */
-int
-puttuple(struct leftist **treep, HeapTuple newtuple, int devnum)
+void
+puttuple(struct leftist **treep,
+	 HeapTuple newtuple,
+	 short devnum,
+	 LeftistContext context)
 {
     register struct	leftist	*new1;
     register struct	leftist	*tp;
     
     new1 = (struct leftist *) palloc((unsigned) sizeof (struct leftist));
-    USEMEM(sizeof (struct leftist));
+    USEMEM(context,sizeof (struct leftist));
     new1->lt_dist = 1;
     new1->lt_devnum = devnum;
     new1->lt_tuple = newtuple;
@@ -185,38 +166,11 @@ puttuple(struct leftist **treep, HeapTuple newtuple, int devnum)
     if ((tp = *treep) == NULL)
 	*treep = new1;
     else
-	*treep = linsert(tp, new1);
-    return(1);
+	*treep = linsert(tp, new1, context);
+    return;
 }
 
 
-/*
- *	dumptuples	- stores all the tuples in tree into file
- */
-void
-dumptuples(FILE *file)
-{
-    register struct	leftist	*tp;
-    register struct	leftist	*newp;
-    HeapTuple	tup;
-    
-    tp = Tuples;
-    while (tp != NULL) {
-	tup = tp->lt_tuple;
-	if (tp->lt_dist == 1)			/* lt_right == NULL */
-	    newp = tp->lt_left;
-	else
-	    newp = lmerge(tp->lt_left, tp->lt_right);
-	FREEMEM(sizeof (struct leftist));
-	FREE(tp);
-	PUTTUP(tup, file);
-	FREEMEM(tup->t_len);
-	FREE(tup);
-	tp = newp;
-    }
-    Tuples = NULL;
-}
-
 /*
  *	tuplecmp	- Compares two tuples with respect CmpList
  *
@@ -225,7 +179,7 @@ dumptuples(FILE *file)
  *	Assumtions:
  */
 int
-tuplecmp(HeapTuple ltup, HeapTuple rtup)
+tuplecmp(HeapTuple ltup, HeapTuple rtup, LeftistContext context)
 {
     register char	*lattr, *rattr;
     int		nkey = 0;
@@ -238,24 +192,27 @@ tuplecmp(HeapTuple ltup, HeapTuple rtup)
 	return(0);
     if (rtup == (HeapTuple)NULL)
 	return(1);
-    while (nkey < Nkeys && !result) {
+    while (nkey < context->nKeys && !result) {
 	lattr = heap_getattr(ltup, InvalidBuffer,
-			     Key[nkey].sk_attno, 
-			     RelationGetTupleDescriptor(SortRdesc),
-			     &isnull);
+			     context->scanKeys[nkey].sk_attno,
+			     context->tupDesc, &isnull);
 	if (isnull)
 	    return(0);
 	rattr = heap_getattr(rtup, InvalidBuffer,
-			     Key[nkey].sk_attno, 
-			     RelationGetTupleDescriptor(SortRdesc),
+			     context->scanKeys[nkey].sk_attno,
+			     context->tupDesc,
 			     &isnull);
 	if (isnull)
 	    return(1);
-	if (Key[nkey].sk_flags & SK_COMMUTE) {
-	    if (!(result = (long) (*Key[nkey].sk_func) (rattr, lattr)))
-		result = -(long) (*Key[nkey].sk_func) (lattr, rattr);
-	} else if (!(result = (long) (*Key[nkey].sk_func) (lattr, rattr)))
-	    result = -(long) (*Key[nkey].sk_func) (rattr, lattr);
+	if (context->scanKeys[nkey].sk_flags & SK_COMMUTE) {
+	    if (!(result =
+		  (long) (*context->scanKeys[nkey].sk_func) (rattr, lattr)))
+		result =
+		    -(long) (*context->scanKeys[nkey].sk_func) (lattr, rattr);
+	} else if (!(result =
+		     (long) (*context->scanKeys[nkey].sk_func) (lattr, rattr)))
+	    result =
+		-(long) (*context->scanKeys[nkey].sk_func) (rattr, lattr);
 	nkey++;
     }
     return (result == 1);
@@ -263,7 +220,7 @@ tuplecmp(HeapTuple ltup, HeapTuple rtup)
 
 #ifdef	EBUG
 void
-checktree(struct leftist *tree)
+checktree(struct leftist *tree, LeftistContext context)
 {
     int		lnodes;
     int		rnodes;
@@ -272,8 +229,8 @@ checktree(struct leftist *tree)
 	puts("Null tree.");
 	return;
     }
-    lnodes = checktreer(tree->lt_left, 1);
-    rnodes = checktreer(tree->lt_right, 1);
+    lnodes = checktreer(tree->lt_left, 1, context);
+    rnodes = checktreer(tree->lt_right, 1, context);
     if (lnodes < 0) {
 	lnodes = -lnodes;
 	puts("0:\tBad left side.");
@@ -297,24 +254,24 @@ checktree(struct leftist *tree)
     } else if (tree->lt_dist != 1+ tree->lt_right->lt_dist)
 	puts("0:\tDistance incorrect.");
     if (lnodes > 0)
-	if (tuplecmp(tree->lt_left->lt_tuple, tree->lt_tuple))
+	if (tuplecmp(tree->lt_left->lt_tuple, tree->lt_tuple, context))
 	    printf("%d:\tLeft child < parent.\n");
     if (rnodes > 0)
-	if (tuplecmp(tree->lt_right->lt_tuple, tree->lt_tuple))
+	if (tuplecmp(tree->lt_right->lt_tuple, tree->lt_tuple, context))
 	    printf("%d:\tRight child < parent.\n");
     printf("Tree has %d nodes\n", 1 + lnodes + rnodes);
 }
 
 int
-checktreer(struct leftist *tree, int level)
+checktreer(struct leftist *tree, int level, LeftistContext context)
 {
     int	lnodes, rnodes;
     int	error = 0;
     
     if (tree == NULL)
 	return(0);
-    lnodes = checktreer(tree->lt_left, level + 1);
-    rnodes = checktreer(tree->lt_right, level + 1);
+    lnodes = checktreer(tree->lt_left, level + 1, context);
+    rnodes = checktreer(tree->lt_right, level + 1, context);
     if (lnodes < 0) {
 	error = 1;
 	lnodes = -lnodes;
@@ -349,12 +306,12 @@ checktreer(struct leftist *tree, int level)
 	printf("%d:\tDistance incorrect.\n", level);
     }
     if (lnodes > 0)
-	if (tuplecmp(tree->lt_left->lt_tuple, tree->lt_tuple)) {
+	if (tuplecmp(tree->lt_left->lt_tuple, tree->lt_tuple, context)) {
 	    error = 1;
 	    printf("%d:\tLeft child < parent.\n");
 	}
     if (rnodes > 0)
-	if (tuplecmp(tree->lt_right->lt_tuple, tree->lt_tuple)) {
+	if (tuplecmp(tree->lt_right->lt_tuple, tree->lt_tuple, context)) {
 	    error = 1;
 	    printf("%d:\tRight child < parent.\n");
 	}

src/include/nodes/execnodes.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: execnodes.h,v 1.6 1996/11/04 08:52:54 scrappy Exp $
+ * $Id: execnodes.h,v 1.7 1997/08/06 03:42:02 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -605,7 +605,7 @@ typedef struct SortState {
     CommonScanState	csstate;	/* its first field is NodeTag */
     bool      		sort_Flag;
     ScanKey   		sort_Keys;
-    Relation  		sort_TempRelation;
+    bool		cleaned;
 } SortState;
 
 /* ----------------

src/include/nodes/plannodes.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: plannodes.h,v 1.5 1996/11/05 08:18:44 scrappy Exp $
+ * $Id: plannodes.h,v 1.6 1997/08/06 03:42:04 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -265,6 +265,8 @@ typedef struct Sort {
     Oid			tempid;
     int			keycount;
     SortState		*sortstate;
+    void		*psortstate;
+    bool		cleaned;
 } Sort;
 
 /* ----------------

src/include/utils/lselect.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: lselect.h,v 1.3 1996/11/04 11:51:19 scrappy Exp $
+ * $Id: lselect.h,v 1.4 1997/08/06 03:42:07 momjian Exp $
  * 
  *-------------------------------------------------------------------------
  */
@@ -14,7 +14,7 @@
 #define	LSELECT_H
 
 #include <stdio.h>
-#include <access/htup.h>
+#include "access/htup.h"
 
 struct	leftist {
     short	lt_dist; 	/* distance to leaf/empty node */
@@ -24,17 +24,26 @@ struct	leftist {
     struct	leftist	*lt_right;
 };
 
-extern	struct	leftist	*Tuples;
+/* replaces global variables in lselect.c to make it reentrant */
+typedef struct {
+    TupleDesc tupDesc;
+    int nKeys;
+    ScanKey scanKeys;
+    int sortMem; /* needed for psort */
+} LeftistContextData;
+typedef LeftistContextData *LeftistContext;
 
-extern struct leftist *lmerge(struct leftist *pt, struct leftist *qt);
-extern HeapTuple gettuple(struct leftist **treep, short *devnum);
-extern int puttuple(struct leftist **treep, HeapTuple newtuple, int devnum);
-extern void dumptuples(FILE *file);
-extern int tuplecmp(HeapTuple ltup, HeapTuple rtup);
+extern struct leftist *lmerge(struct leftist *pt, struct leftist *qt,
+    LeftistContext context);
+extern HeapTuple gettuple(struct leftist **treep, short *devnum,
+    LeftistContext context);
+extern void puttuple(struct leftist **treep, HeapTuple newtuple, short devnum,
+    LeftistContext context);
+extern int tuplecmp(HeapTuple ltup, HeapTuple rtup, LeftistContext context);
 
 #ifdef EBUG
-extern void checktree(struct leftist *tree);
-extern int checktreer(struct leftist *tree, int level);
+extern void checktree(struct leftist *tree, LeftistContext context);
+extern int checktreer(struct leftist *tree, int level, LeftistContext context);
 #endif /* EBUG */
 
 #endif 	/* LSELECT_H */

src/include/utils/psort.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: psort.h,v 1.3 1997/05/20 11:37:33 vadim Exp $
+ * $Id: psort.h,v 1.4 1997/08/06 03:42:13 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -14,11 +14,13 @@
 #define	PSORT_H
 
 #include <stdio.h>
-#include <access/relscan.h>
+#include "access/relscan.h"
+#include "utils/lselect.h"
+#include "nodes/plannodes.h"
 
 #define	SORTMEM		(1 << 18)		/* 1/4 M - any static memory */
 #define	MAXTAPES	7			/* 7--See Fig. 70, p273 */
-#define	TAPEEXT		"pg_psort.XXXXXX"	/* TEMPDIR/TAPEEXT */
+#define	TAPEEXTLEN	strlen("pg_psort.xxxxx.xxx")	/* TEMPDIR/TAPEEXT */
 #define	FREE(x)		pfree((char *) x)
 
 struct	tape {
@@ -35,13 +37,38 @@ struct	cmplist {
     struct	cmplist		*cp_next; /* next in chain */
 };
 
-extern	int		Nkeys;
-extern	ScanKey		key;
-extern	int		SortMemory;	/* free memory */
-extern	Relation	SortRdesc;
-extern	struct leftist	*Tuples;
+/* This structure preserves the state of psort between calls from different
+ * nodes to its interface functions. Basically, it includes all of the global
+ * variables in psort. In case you were wondering, pointers to these structures
+ * are included in Sort node structures.			-Rex 2.6.1995
+ */
+typedef struct Psortstate {
+    LeftistContextData treeContext;
+
+    int TapeRange;
+    int Level;
+    int TotalDummy;
+    struct tape Tape[MAXTAPES];
+
+    int BytesRead;
+    int BytesWritten;
+    int tupcount;
+
+    struct leftist *Tuples;
+
+    FILE *psort_grab_file;
+    long psort_current;	/* could be file offset, or array index */
+    long psort_saved;	/* could be file offset, or array index */
+    bool using_tape_files;
+
+    HeapTuple *memtuples;
+} Psortstate;
 
 #ifdef	EBUG
+#include <stdio.h>
+#include "utils/elog.h"
+#include "storage/buf.h"
+#include "storage/bufmgr.h"
 
 #define	PDEBUG(PROC, S1)\
 elog(DEBUG, "%s:%d>> PROC: %s.", __FILE__, __LINE__, S1)
@@ -69,15 +96,21 @@ if (1) CODE; else
 #endif
 
 /* psort.c */
-extern void psort(Relation oldrel, Relation newrel, int nkeys, ScanKey key);
-extern void initpsort(void);
+extern bool psort_begin(Sort *node, int nkeys, ScanKey key);
+extern void inittapes(Sort *node);
 extern void resetpsort(void);
-extern void initialrun(Relation rdesc);
-extern bool createrun(HeapScanDesc sdesc, FILE *file);
-extern HeapTuple tuplecopy(HeapTuple tup, Relation rdesc, Buffer b);
-extern FILE *mergeruns(void);
-extern void merge(struct tape *dest);
-extern void endpsort(Relation rdesc, FILE *file);
+extern void initialrun(Sort *node, bool *empty);
+extern bool createrun(Sort *node, FILE *file, bool *empty);
+extern HeapTuple tuplecopy(HeapTuple tup);
+extern FILE *mergeruns(Sort *node);
+extern void merge(Sort *node, struct tape *dest);
+
+extern void dumptuples(Sort *node);
+extern HeapTuple psort_grabtuple(Sort *node);
+extern void psort_markpos(Sort *node);
+extern void psort_restorepos(Sort *node);
+extern void psort_end(Sort *node);
+
 extern FILE *gettape(void);
 extern void resettape(FILE *file);
 extern void destroytape(FILE *file);

src/man/postgres.1

 .\" This is -*-nroff-*-
 .\" XXX standard disclaimer belongs here....
-.\" $Header: /cvsroot/pgsql/src/man/Attic/postgres.1,v 1.5 1997/01/26 15:32:20 scrappy Exp $
+.\" $Header: /cvsroot/pgsql/src/man/Attic/postgres.1,v 1.6 1997/08/06 03:42:18 momjian Exp $
 .TH POSTGRES95 UNIX 12/08/96 Postgres95 Postgres95
 .SH NAME
 postgres \(em the Postgres backend server
@@ -79,7 +79,10 @@ is the number of shared-memory buffers that the
 .IR "postmaster"
 has allocated for the backend server processes that it starts.  If the
 backend is running standalone, this specifies the number of buffers to
-allocate.  This value defaults to 64.
+allocate.  This value defaults to 64, and each buffer is 8k bytes.
+.TP
+.BR "-E"
+Echo all queries.
 .TP
 .BR "-F"
 Disable automatic fsync() call after each transaction.
@@ -96,8 +99,10 @@ useful for interactive use.
 .BR "-Q"
 Specifies \*(lqquiet\*(rq mode.
 .TP
-.BR "-E"
-Echo all queries.
+.BR "-S"
+Specifies the amount of memory to be used by internal sorts before using
+disk files for sorting.  This value is specified in 1k bytes, and
+defaults to 512.
 .TP
 .BR "-e"
 The
@@ -154,15 +159,6 @@ Turns off the locking system.
 .BR "-N"
 Disables use of newline as a query delimiter.
 .TP
-.BR "-S"
-Indicates that the transaction system can run with the assumption of
-stable main memory, thereby avoiding the necessary flushing of data
-and log pages to disk at the end of each transaction system.  This is
-only used for performance comparisons for stable vs. non-stable
-storage.  Do not use this in other cases, as recovery after a system
-crash may be impossible when this option is specified in the absence
-of stable main memory.
-.TP
 .BR "-b"
 Enables generation of bushy query plan trees (as opposed to left-deep
 query plans trees).  These query plans are not intended for actual

src/man/postmaster.1

 .\" This is -*-nroff-*-
 .\" XXX standard disclaimer belongs here....
-.\" $Header: /cvsroot/pgsql/src/man/Attic/postmaster.1,v 1.5 1997/02/19 01:31:30 momjian Exp $
+.\" $Header: /cvsroot/pgsql/src/man/Attic/postmaster.1,v 1.6 1997/08/06 03:42:21 momjian Exp $
 .TH POSTMASTER UNIX 11/05/95 PostgreSQL PostgreSQL
 .SH "NAME"
 postmaster \(em run the Postgres postmaster
@@ -60,7 +60,7 @@ understands the following command-line options:
 is the number of shared-memory buffers for the 
 .IR "postmaster"
 to allocate and manage for the backend server processes that it
-starts.  This value defaults to 64.
+starts.  This value defaults to 64, and each buffer is 8k bytes.
 .TP
 .BR "-D" " data_dir"
 Specifies the directory to use as the root of the tree of database