PostgreSQL Source Code git master
hashsort.c File Reference
#include "postgres.h"
#include "access/hash.h"
#include "commands/progress.h"
#include "miscadmin.h"
#include "pgstat.h"
#include "port/pg_bitutils.h"
#include "utils/tuplesort.h"
Include dependency graph for hashsort.c:

Go to the source code of this file.

Data Structures

struct  HSpool
 

Functions

HSpool_h_spoolinit (Relation heap, Relation index, uint32 num_buckets)
 
void _h_spooldestroy (HSpool *hspool)
 
void _h_spool (HSpool *hspool, ItemPointer self, const Datum *values, const bool *isnull)
 
void _h_indexbuild (HSpool *hspool, Relation heapRel)
 

Function Documentation

◆ _h_indexbuild()

void _h_indexbuild ( HSpool hspool,
Relation  heapRel 
)

Definition at line 120 of file hashsort.c.

121{
122 IndexTuple itup;
123 int64 tups_done = 0;
124#ifdef USE_ASSERT_CHECKING
125 uint32 hashkey = 0;
126#endif
127
129
130 while ((itup = tuplesort_getindextuple(hspool->sortstate, true)) != NULL)
131 {
132 /*
133 * Technically, it isn't critical that hash keys be found in sorted
134 * order, since this sorting is only used to increase locality of
135 * access as a performance optimization. It still seems like a good
136 * idea to test tuplesort.c's handling of hash index tuple sorts
137 * through an assertion, though.
138 */
139#ifdef USE_ASSERT_CHECKING
140 uint32 lasthashkey = hashkey;
141
143 hspool->max_buckets, hspool->high_mask,
144 hspool->low_mask);
145 Assert(hashkey >= lasthashkey);
146#endif
147
148 /* the tuples are sorted by hashkey, so pass 'sorted' as true */
149 _hash_doinsert(hspool->index, itup, heapRel, true);
150
151 /* allow insertion phase to be interrupted, and track progress */
153
155 ++tups_done);
156 }
157}
void pgstat_progress_update_param(int index, int64 val)
int64_t int64
Definition: c.h:499
uint32_t uint32
Definition: c.h:502
Assert(PointerIsAligned(start, uint64))
void _hash_doinsert(Relation rel, IndexTuple itup, Relation heapRel, bool sorted)
Definition: hashinsert.c:38
uint32 _hash_get_indextuple_hashkey(IndexTuple itup)
Definition: hashutil.c:291
Bucket _hash_hashkey2bucket(uint32 hashkey, uint32 maxbucket, uint32 highmask, uint32 lowmask)
Definition: hashutil.c:125
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:122
#define PROGRESS_CREATEIDX_TUPLES_DONE
Definition: progress.h:90
uint32 low_mask
Definition: hashsort.c:51
Tuplesortstate * sortstate
Definition: hashsort.c:41
uint32 high_mask
Definition: hashsort.c:50
uint32 max_buckets
Definition: hashsort.c:52
Relation index
Definition: hashsort.c:42
void tuplesort_performsort(Tuplesortstate *state)
Definition: tuplesort.c:1363
IndexTuple tuplesort_getindextuple(Tuplesortstate *state, bool forward)

References _hash_doinsert(), _hash_get_indextuple_hashkey(), _hash_hashkey2bucket(), Assert(), CHECK_FOR_INTERRUPTS, HSpool::high_mask, HSpool::index, HSpool::low_mask, HSpool::max_buckets, pgstat_progress_update_param(), PROGRESS_CREATEIDX_TUPLES_DONE, HSpool::sortstate, tuplesort_getindextuple(), and tuplesort_performsort().

Referenced by hashbuild().

◆ _h_spool()

void _h_spool ( HSpool hspool,
ItemPointer  self,
const Datum values,
const bool *  isnull 
)

Definition at line 109 of file hashsort.c.

110{
112 self, values, isnull);
113}
static Datum values[MAXATTR]
Definition: bootstrap.c:151
void tuplesort_putindextuplevalues(Tuplesortstate *state, Relation rel, ItemPointer self, const Datum *values, const bool *isnull)

References HSpool::index, HSpool::sortstate, tuplesort_putindextuplevalues(), and values.

Referenced by hashbuildCallback().

◆ _h_spooldestroy()

void _h_spooldestroy ( HSpool hspool)

Definition at line 99 of file hashsort.c.

100{
101 tuplesort_end(hspool->sortstate);
102 pfree(hspool);
103}
void pfree(void *pointer)
Definition: mcxt.c:1524
void tuplesort_end(Tuplesortstate *state)
Definition: tuplesort.c:951

References pfree(), HSpool::sortstate, and tuplesort_end().

Referenced by hashbuild().

◆ _h_spoolinit()

HSpool * _h_spoolinit ( Relation  heap,
Relation  index,
uint32  num_buckets 
)

Definition at line 60 of file hashsort.c.

61{
62 HSpool *hspool = (HSpool *) palloc0(sizeof(HSpool));
63
64 hspool->index = index;
65
66 /*
67 * Determine the bitmask for hash code values. Since there are currently
68 * num_buckets buckets in the index, the appropriate mask can be computed
69 * as follows.
70 *
71 * NOTE : This hash mask calculation should be in sync with similar
72 * calculation in _hash_init_metabuffer.
73 */
74 hspool->high_mask = pg_nextpower2_32(num_buckets + 1) - 1;
75 hspool->low_mask = (hspool->high_mask >> 1);
76 hspool->max_buckets = num_buckets - 1;
77
78 /*
79 * We size the sort area as maintenance_work_mem rather than work_mem to
80 * speed index creation. This should be OK since a single backend can't
81 * run multiple index creations in parallel.
82 */
84 index,
85 hspool->high_mask,
86 hspool->low_mask,
87 hspool->max_buckets,
89 NULL,
91
92 return hspool;
93}
int maintenance_work_mem
Definition: globals.c:132
void * palloc0(Size size)
Definition: mcxt.c:1347
static uint32 pg_nextpower2_32(uint32 num)
Definition: pg_bitutils.h:189
Definition: type.h:96
#define TUPLESORT_NONE
Definition: tuplesort.h:94
Tuplesortstate * tuplesort_begin_index_hash(Relation heapRel, Relation indexRel, uint32 high_mask, uint32 low_mask, uint32 max_buckets, int workMem, SortCoordinate coordinate, int sortopt)

References HSpool::high_mask, HSpool::index, HSpool::low_mask, maintenance_work_mem, HSpool::max_buckets, palloc0(), pg_nextpower2_32(), HSpool::sortstate, tuplesort_begin_index_hash(), and TUPLESORT_NONE.

Referenced by hashbuild().