1. Use qsort for first run
2. Limit number of tuples in leftist trees: - put one tuple from current tree to disk if limit reached; - end run creation if limit reached by nextrun. 3. Avoid mergeruns() if first run is single one!
This commit is contained in:
Vadim B. Mikheev
parent
303f6514bd
commit
712ea2507e
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/sort/Attic/lselect.c,v 1.8 1997/09/12 04:08:46 momjian Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/sort/Attic/lselect.c,v 1.9 1997/09/18 05:37:30 vadim Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -26,15 +26,6 @@
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#include "utils/psort.h"
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#include "utils/lselect.h"
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#define PUTTUP(TUP, FP) fwrite((char *)TUP, (TUP)->t_len, 1, FP)
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/*
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* USEMEM - record use of memory
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* FREEMEM - record freeing of memory
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*/
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#define USEMEM(context,AMT) context->sortMem -= (AMT)
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#define FREEMEM(context,AMT) context->sortMem += (AMT)
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/*
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* lmerge - merges two leftist trees into one
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*
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@ -149,8 +140,7 @@ gettuple(struct leftist ** treep,
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else
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*treep = lmerge(tp->lt_left, tp->lt_right, context);
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FREEMEM(context, sizeof(struct leftist));
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FREE(tp);
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pfree (tp);
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return (tup);
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}
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@ -173,7 +163,6 @@ puttuple(struct leftist ** treep,
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register struct leftist *tp;
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new1 = (struct leftist *) palloc((unsigned) sizeof(struct leftist));
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USEMEM(context, sizeof(struct leftist));
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new1->lt_dist = 1;
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new1->lt_devnum = devnum;
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new1->lt_tuple = newtuple;
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@ -7,7 +7,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/sort/Attic/psort.c,v 1.22 1997/09/15 14:28:42 vadim Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/sort/Attic/psort.c,v 1.23 1997/09/18 05:37:31 vadim Exp $
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*
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* NOTES
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* Sorts the first relation into the second relation.
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@ -64,15 +64,17 @@
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#include "miscadmin.h"
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#include "storage/fd.h"
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static bool createrun(Sort *node, FILE *file, bool *empty);
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static void destroytape(FILE *file);
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static void dumptuples(FILE *file, Sort *node);
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static bool createfirstrun(Sort * node);
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static bool createrun(Sort * node, FILE * file);
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static void destroytape(FILE * file);
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static void dumptuples(FILE * file, Sort * node);
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static FILE *gettape(void);
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static void initialrun(Sort *node, bool *empty);
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static void inittapes(Sort *node);
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static void merge(Sort *node, struct tape * dest);
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static FILE *mergeruns(Sort *node);
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static void initialrun(Sort * node);
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static void inittapes(Sort * node);
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static void merge(Sort * node, struct tape * dest);
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static FILE *mergeruns(Sort * node);
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static HeapTuple tuplecopy(HeapTuple tup);
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static int _psort_cmp (HeapTuple *ltup, HeapTuple *rtup);
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@ -80,6 +82,10 @@ static HeapTuple tuplecopy(HeapTuple tup);
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static long shortzero = 0; /* used to delimit runs */
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static TupleDesc PsortTupDesc;
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static ScanKey PsortKeys; /* used by _psort_cmp */
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static int PsortNkeys;
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/*
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* old psort global variables
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*
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@ -123,9 +129,8 @@ static long shortzero = 0; /* used to delimit runs */
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* Allocates and initializes sort node's psort state.
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*/
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bool
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psort_begin(Sort *node, int nkeys, ScanKey key)
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psort_begin(Sort * node, int nkeys, ScanKey key)
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{
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bool empty; /* to answer: is child node empty? */
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node->psortstate = (struct Psortstate *) palloc(sizeof(struct Psortstate));
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@ -142,17 +147,20 @@ psort_begin(Sort *node, int nkeys, ScanKey key)
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PS(node)->treeContext.sortMem = SortMem * 1024;
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PS(node)->Tuples = NULL;
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PS(node)->lasttuple = NULL;
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PS(node)->lt_tupcount = 0;
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PS(node)->tupcount = 0;
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PS(node)->using_tape_files = false;
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PS(node)->psort_grab_file = NULL;
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PS(node)->memtuples = NULL;
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initialrun(node, &empty);
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initialrun(node);
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if (empty)
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if (PS(node)->tupcount == 0)
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return false;
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if (PS(node)->using_tape_files)
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if (PS(node)->using_tape_files && PS(node)->psort_grab_file == NULL)
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PS(node)->psort_grab_file = mergeruns(node);
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PS(node)->psort_current = 0;
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@ -168,7 +176,7 @@ psort_begin(Sort *node, int nkeys, ScanKey key)
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* number of allocated tapes
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*/
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static void
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inittapes(Sort *node)
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inittapes(Sort * node)
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{
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register int i;
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register struct tape *tp;
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@ -266,7 +274,7 @@ inittapes(Sort *node)
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* Also, perhaps allocate tapes when needed. Split into 2 funcs.
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*/
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static void
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initialrun(Sort *node, bool *empty)
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initialrun(Sort * node)
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{
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/* register struct tuple *tup; */
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register struct tape *tp;
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@ -278,20 +286,27 @@ initialrun(Sort *node, bool *empty)
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tp = PS(node)->Tape;
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if ((bool) createrun(node, NULL, empty) != false)
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if (createfirstrun(node))
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{
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if (!PS(node)->using_tape_files)
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inittapes(node);
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Assert (PS(node)->using_tape_files);
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extrapasses = 0;
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}
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else
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else /* all tuples fetched */
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{
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/* if empty or rows fit in memory, we never access tape stuff */
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if (*empty || !PS(node)->using_tape_files)
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if ( !PS(node)->using_tape_files ) /* empty or sorted in memory */
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return;
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if (!PS(node)->using_tape_files)
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inittapes(node);
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extrapasses = 1 + (PS(node)->Tuples != NULL); /* (T != N) ? 2 : 1 */
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/*
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* if PS(node)->Tuples == NULL then we have single (sorted) run
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* which can be used as result grab file! So, we may avoid
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* mergeruns - it will just copy this run to new file.
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*/
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if ( PS(node)->Tuples == NULL )
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{
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PS(node)->psort_grab_file = PS(node)->Tape->tp_file;
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rewind (PS(node)->psort_grab_file);
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return;
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}
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extrapasses = 2;
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}
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for (;;)
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@ -328,7 +343,7 @@ initialrun(Sort *node, bool *empty)
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else
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break;
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if ((bool) createrun(node, tp->tp_file, empty) == false)
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if ((bool) createrun(node, tp->tp_file) == false)
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extrapasses = 1 + (PS(node)->Tuples != NULL);
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/* D2 */
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}
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@ -336,6 +351,138 @@ initialrun(Sort *node, bool *empty)
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rewind(tp->tp_file); /* D. */
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}
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/*
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* createfirstrun - tries to sort tuples in memory using qsort
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* until LACKMEM; if not enough memory then switches
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* to tape method
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*
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* Returns:
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* FALSE iff process through end of relation
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* Tuples contains the tuples for the following run upon exit
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*/
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static bool
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createfirstrun(Sort *node)
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{
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HeapTuple tup;
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bool foundeor = false;
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HeapTuple *memtuples;
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int t_last = -1;
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int t_free = 1000;
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TupleTableSlot *cr_slot;
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Assert(node != (Sort *) NULL);
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Assert(PS(node) != (Psortstate *) NULL);
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Assert(!PS(node)->using_tape_files);
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Assert(PS(node)->memtuples == NULL);
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Assert(PS(node)->tupcount == 0);
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if (LACKMEM(node))
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elog (FATAL, "psort: LACKMEM in createfirstrun");
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memtuples = palloc(t_free * sizeof(HeapTuple));
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for (;;)
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{
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if ( LACKMEM (node) )
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break;
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/*
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* About to call ExecProcNode, it can mess up the state if it
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* eventually calls another Sort node. So must stow it away here
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* for the meantime. -Rex
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* 2.2.1995
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*/
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cr_slot = ExecProcNode(outerPlan((Plan *) node), (Plan *) node);
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if (TupIsNull(cr_slot))
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{
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foundeor = true;
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break;
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}
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tup = tuplecopy(cr_slot->val);
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ExecClearTuple(cr_slot);
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IncrProcessed();
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USEMEM(node, tup->t_len);
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TRACEMEM(createfirstrun);
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if ( t_free <= 0 )
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{
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t_free = 1000;
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memtuples = repalloc (memtuples,
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(t_last + t_free + 1) * sizeof (HeapTuple));
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}
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t_last++;
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t_free--;
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memtuples[t_last] = tup;
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}
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if ( t_last < 0 ) /* empty */
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{
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Assert (foundeor);
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pfree (memtuples);
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return (false);
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}
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t_last++;
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PS(node)->tupcount = t_last;
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PsortTupDesc = PS(node)->treeContext.tupDesc;
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PsortKeys = PS(node)->treeContext.scanKeys;
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PsortNkeys = PS(node)->treeContext.nKeys;
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qsort (memtuples, t_last, sizeof (HeapTuple),
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(int (*)(const void *,const void *))_psort_cmp);
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if ( LACKMEM (node) ) /* in-memory sort is impossible */
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{
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register int t;
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register int f;
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FILE *file;
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Assert (!foundeor);
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inittapes(node);
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file = PS(node)->Tape->tp_file;
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/* put extra tuples into tape file */
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if ( t_last > SortTuplesInTree )
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{
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register HeapTuple lasttuple;
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t = t_last - SortTuplesInTree;
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for (f = 0, lasttuple = NULL; f < t; f++)
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{
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if ( lasttuple )
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{
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FREEMEM(node, lasttuple->t_len);
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FREE(lasttuple);
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TRACEMEM(createfirstrun);
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}
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lasttuple = memtuples[f];
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PUTTUP(node, lasttuple, file);
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TRACEOUT(createfirstrun, lasttuple);
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}
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PS(node)->lasttuple = lasttuple;
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}
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else
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{
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PS(node)->lasttuple = NULL;
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f = 0;
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}
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/* put rest of tuples into leftist tree for createrun */
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for (t = t_last - 1 ; t >= f; t--)
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puttuple(&PS(node)->Tuples, memtuples[t], 0, &PS(node)->treeContext);
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PS(node)->lt_tupcount = t_last - f;
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pfree (memtuples);
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foundeor = !createrun (node, file);
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}
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else
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{
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Assert (foundeor);
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PS(node)->memtuples = memtuples;
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}
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return (!foundeor);
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}
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/*
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* createrun - places the next run on file, grabbing the tuples by
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* executing the subplan passed in
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@ -348,13 +495,15 @@ initialrun(Sort *node, bool *empty)
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* Tuples contains the tuples for the following run upon exit
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*/
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static bool
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createrun(Sort *node, FILE *file, bool *empty)
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createrun(Sort * node, FILE * file)
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{
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register HeapTuple lasttuple;
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register HeapTuple tup;
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struct leftist *nextrun;
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bool foundeor;
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short junk;
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int curr_tupcount = (PS(node)->Tuples != NULL) ? PS(node)->lt_tupcount : 0;
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int next_tupcount = 0;
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int cr_tuples = 0; /* Count tuples grabbed from plannode */
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TupleTableSlot *cr_slot;
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@ -362,33 +511,36 @@ createrun(Sort *node, FILE *file, bool *empty)
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Assert(node != (Sort *) NULL);
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Assert(PS(node) != (Psortstate *) NULL);
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lasttuple = NULL;
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lasttuple = PS(node)->lasttuple; /* !NULL if called from createfirstrun */
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nextrun = NULL;
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foundeor = false;
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for (;;)
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{
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while (LACKMEM(node) && PS(node)->Tuples != NULL)
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if ((LACKMEM(node) && PS(node)->Tuples != NULL) || curr_tupcount > SortTuplesInTree)
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{
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if (lasttuple != NULL)
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do
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{
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FREEMEM(node, lasttuple->t_len);
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FREE(lasttuple);
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TRACEMEM(createrun);
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}
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lasttuple = tup = gettuple(&PS(node)->Tuples, &junk,
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&PS(node)->treeContext);
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if (!PS(node)->using_tape_files)
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{
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inittapes(node);
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if (!file)
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file = PS(node)->Tape->tp_file; /* was NULL */
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}
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PUTTUP(node, tup, file);
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TRACEOUT(createrun, tup);
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if (lasttuple != NULL)
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{
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FREEMEM(node, lasttuple->t_len);
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FREE(lasttuple);
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TRACEMEM(createrun);
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}
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lasttuple = tup = gettuple(&PS(node)->Tuples, &junk,
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&PS(node)->treeContext);
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Assert (PS(node)->using_tape_files);
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PUTTUP(node, tup, file);
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TRACEOUT(createrun, tup);
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curr_tupcount--;
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} while (LACKMEM(node) && PS(node)->Tuples != NULL);
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}
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if (LACKMEM(node))
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break;
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if ( next_tupcount >= SortTuplesInTree )
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break;
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/*
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* About to call ExecProcNode, it can mess up the state if it
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* eventually calls another Sort node. So must stow it away here
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@ -416,9 +568,15 @@ createrun(Sort *node, FILE *file, bool *empty)
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TRACEMEM(createrun);
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if (lasttuple != NULL && tuplecmp(tup, lasttuple,
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&PS(node)->treeContext))
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{
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puttuple(&nextrun, tup, 0, &PS(node)->treeContext);
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next_tupcount++;
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}
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else
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{
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puttuple(&PS(node)->Tuples, tup, 0, &PS(node)->treeContext);
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curr_tupcount++;
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}
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}
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if (lasttuple != NULL)
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{
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@ -427,15 +585,13 @@ createrun(Sort *node, FILE *file, bool *empty)
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TRACEMEM(createrun);
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}
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dumptuples(file, node);
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if (PS(node)->using_tape_files)
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ENDRUN(file);
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ENDRUN(file);
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/* delimit the end of the run */
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PS(node)->Tuples = nextrun;
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PS(node)->lt_tupcount = next_tupcount;
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PS(node)->lasttuple = NULL;
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/* if we did not see any tuples, mark empty */
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*empty = (cr_tuples > 0) ? false : true;
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return ((bool) !foundeor); /* XXX - works iff bool is {0,1} */
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return ((bool) ! foundeor); /* XXX - works iff bool is {0,1} */
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}
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/*
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@ -466,7 +622,7 @@ tuplecopy(HeapTuple tup)
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* file of tuples in order
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*/
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static FILE *
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mergeruns(Sort *node)
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mergeruns(Sort * node)
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{
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register struct tape *tp;
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@ -493,7 +649,7 @@ mergeruns(Sort *node)
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* (polyphase merge Alg.D(D5)--Knuth, Vol.3, p271)
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*/
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static void
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merge(Sort *node, struct tape * dest)
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merge(Sort * node, struct tape * dest)
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{
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register HeapTuple tup;
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register struct tape *lasttp; /* (TAPE[P]) */
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|
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@ -600,20 +756,15 @@ merge(Sort *node, struct tape * dest)
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* dumptuples - stores all the tuples in tree into file
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*/
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static void
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dumptuples(FILE *file, Sort *node)
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dumptuples(FILE * file, Sort * node)
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{
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register struct leftist *tp;
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register struct leftist *newp;
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struct leftist **treep = &PS(node)->Tuples;
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LeftistContext context = &PS(node)->treeContext;
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HeapTuple tup;
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int memtupindex = 0;
|
||||
|
||||
if (!PS(node)->using_tape_files && PS(node)->tupcount)
|
||||
{
|
||||
Assert(PS(node)->memtuples == NULL);
|
||||
PS(node)->memtuples = palloc(PS(node)->tupcount * sizeof(HeapTuple));
|
||||
}
|
||||
Assert (PS(node)->using_tape_files);
|
||||
|
||||
tp = *treep;
|
||||
while (tp != NULL)
|
||||
|
|
@ -625,14 +776,9 @@ dumptuples(FILE *file, Sort *node)
|
|||
newp = lmerge(tp->lt_left, tp->lt_right, context);
|
||||
FREEMEM(node, sizeof(struct leftist));
|
||||
FREE(tp);
|
||||
if (PS(node)->using_tape_files)
|
||||
{
|
||||
PUTTUP(node, tup, file);
|
||||
FREEMEM(node, tup->t_len);
|
||||
FREE(tup);
|
||||
}
|
||||
else
|
||||
PS(node)->memtuples[memtupindex++] = tup;
|
||||
PUTTUP(node, tup, file);
|
||||
FREEMEM(node, tup->t_len);
|
||||
FREE(tup);
|
||||
|
||||
tp = newp;
|
||||
}
|
||||
|
|
@ -646,7 +792,7 @@ dumptuples(FILE *file, Sort *node)
|
|||
* a NULL indicating the last tuple has been processed.
|
||||
*/
|
||||
HeapTuple
|
||||
psort_grabtuple(Sort *node, bool *should_free)
|
||||
psort_grabtuple(Sort * node, bool * should_free)
|
||||
{
|
||||
register HeapTuple tup;
|
||||
long tuplen;
|
||||
|
|
@ -691,7 +837,7 @@ psort_grabtuple(Sort *node, bool *should_free)
|
|||
* psort_markpos - saves current position in the merged sort file
|
||||
*/
|
||||
void
|
||||
psort_markpos(Sort *node)
|
||||
psort_markpos(Sort * node)
|
||||
{
|
||||
Assert(node != (Sort *) NULL);
|
||||
Assert(PS(node) != (Psortstate *) NULL);
|
||||
|
|
@ -704,7 +850,7 @@ psort_markpos(Sort *node)
|
|||
* last saved position
|
||||
*/
|
||||
void
|
||||
psort_restorepos(Sort *node)
|
||||
psort_restorepos(Sort * node)
|
||||
{
|
||||
Assert(node != (Sort *) NULL);
|
||||
Assert(PS(node) != (Psortstate *) NULL);
|
||||
|
|
@ -719,13 +865,14 @@ psort_restorepos(Sort *node)
|
|||
* called unless psort_grabtuple has returned a NULL.
|
||||
*/
|
||||
void
|
||||
psort_end(Sort *node)
|
||||
psort_end(Sort * node)
|
||||
{
|
||||
register struct tape *tp;
|
||||
|
||||
if (!node->cleaned)
|
||||
{
|
||||
Assert(node != (Sort *) NULL);
|
||||
|
||||
/*
|
||||
* I'm changing this because if we are sorting a relation with no
|
||||
* tuples, psortstate is NULL.
|
||||
|
|
@ -818,7 +965,7 @@ gettape()
|
|||
*/
|
||||
#ifdef NOT_USED
|
||||
static void
|
||||
resettape(FILE *file)
|
||||
resettape(FILE * file)
|
||||
{
|
||||
register struct tapelst *tp;
|
||||
register int fd;
|
||||
|
|
@ -850,7 +997,7 @@ resettape(FILE *file)
|
|||
* Exits instead of returning status, if given invalid tape.
|
||||
*/
|
||||
static void
|
||||
destroytape(FILE *file)
|
||||
destroytape(FILE * file)
|
||||
{
|
||||
register struct tapelst *tp,
|
||||
*tq;
|
||||
|
|
@ -885,3 +1032,42 @@ destroytape(FILE *file)
|
|||
tp = tp->tl_next;
|
||||
}
|
||||
}
|
||||
|
||||
static int
|
||||
_psort_cmp (HeapTuple *ltup, HeapTuple *rtup)
|
||||
{
|
||||
register Datum lattr, rattr;
|
||||
int nkey = 0;
|
||||
int result = 0;
|
||||
bool isnull1, isnull2;
|
||||
|
||||
while ( nkey < PsortNkeys && !result )
|
||||
{
|
||||
lattr = heap_getattr(*ltup, InvalidBuffer,
|
||||
PsortKeys[nkey].sk_attno,
|
||||
PsortTupDesc,
|
||||
&isnull1);
|
||||
rattr = heap_getattr(*rtup, InvalidBuffer,
|
||||
PsortKeys[nkey].sk_attno,
|
||||
PsortTupDesc,
|
||||
&isnull2);
|
||||
if ( isnull1 )
|
||||
{
|
||||
if ( isnull2 )
|
||||
return (0);
|
||||
return(1);
|
||||
}
|
||||
else if ( isnull2 )
|
||||
return (-1);
|
||||
|
||||
if (PsortKeys[nkey].sk_flags & SK_COMMUTE)
|
||||
{
|
||||
if (!(result = -(long) (*PsortKeys[nkey].sk_func) (rattr, lattr)))
|
||||
result = (long) (*PsortKeys[nkey].sk_func) (lattr, rattr);
|
||||
}
|
||||
else if (!(result = -(long) (*PsortKeys[nkey].sk_func) (lattr, rattr)))
|
||||
result = (long) (*PsortKeys[nkey].sk_func) (rattr, lattr);
|
||||
nkey++;
|
||||
}
|
||||
return (result);
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue