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nodeGatherMerge.c File Reference
#include "postgres.h"
#include "executor/executor.h"
#include "executor/execParallel.h"
#include "executor/nodeGatherMerge.h"
#include "executor/tqueue.h"
#include "lib/binaryheap.h"
#include "miscadmin.h"
#include "optimizer/optimizer.h"
Include dependency graph for nodeGatherMerge.c:

Go to the source code of this file.

Data Structures

struct  GMReaderTupleBuffer
 

Macros

#define MAX_TUPLE_STORE   10
 

Typedefs

typedef struct GMReaderTupleBuffer GMReaderTupleBuffer
 
typedef int32 SlotNumber
 

Functions

static TupleTableSlotExecGatherMerge (PlanState *pstate)
 
static int32 heap_compare_slots (Datum a, Datum b, void *arg)
 
static TupleTableSlotgather_merge_getnext (GatherMergeState *gm_state)
 
static MinimalTuple gm_readnext_tuple (GatherMergeState *gm_state, int nreader, bool nowait, bool *done)
 
static void ExecShutdownGatherMergeWorkers (GatherMergeState *node)
 
static void gather_merge_setup (GatherMergeState *gm_state)
 
static void gather_merge_init (GatherMergeState *gm_state)
 
static void gather_merge_clear_tuples (GatherMergeState *gm_state)
 
static bool gather_merge_readnext (GatherMergeState *gm_state, int reader, bool nowait)
 
static void load_tuple_array (GatherMergeState *gm_state, int reader)
 
GatherMergeStateExecInitGatherMerge (GatherMerge *node, EState *estate, int eflags)
 
void ExecEndGatherMerge (GatherMergeState *node)
 
void ExecShutdownGatherMerge (GatherMergeState *node)
 
void ExecReScanGatherMerge (GatherMergeState *node)
 

Macro Definition Documentation

◆ MAX_TUPLE_STORE

#define MAX_TUPLE_STORE   10

Definition at line 31 of file nodeGatherMerge.c.

Typedef Documentation

◆ GMReaderTupleBuffer

◆ SlotNumber

typedef int32 SlotNumber

Definition at line 746 of file nodeGatherMerge.c.

Function Documentation

◆ ExecEndGatherMerge()

void ExecEndGatherMerge ( GatherMergeState node)

Definition at line 291 of file nodeGatherMerge.c.

292{
293 ExecEndNode(outerPlanState(node)); /* let children clean up first */
295}
void ExecEndNode(PlanState *node)
Definition: execProcnode.c:562
#define outerPlanState(node)
Definition: execnodes.h:1222
void ExecShutdownGatherMerge(GatherMergeState *node)

References ExecEndNode(), ExecShutdownGatherMerge(), and outerPlanState.

Referenced by ExecEndNode().

◆ ExecGatherMerge()

static TupleTableSlot * ExecGatherMerge ( PlanState pstate)
static

Definition at line 183 of file nodeGatherMerge.c.

184{
186 TupleTableSlot *slot;
187 ExprContext *econtext;
188
190
191 /*
192 * As with Gather, we don't launch workers until this node is actually
193 * executed.
194 */
195 if (!node->initialized)
196 {
197 EState *estate = node->ps.state;
198 GatherMerge *gm = castNode(GatherMerge, node->ps.plan);
199
200 /*
201 * Sometimes we might have to run without parallelism; but if parallel
202 * mode is active then we can try to fire up some workers.
203 */
204 if (gm->num_workers > 0 && estate->es_use_parallel_mode)
205 {
206 ParallelContext *pcxt;
207
208 /* Initialize, or re-initialize, shared state needed by workers. */
209 if (!node->pei)
211 estate,
212 gm->initParam,
213 gm->num_workers,
214 node->tuples_needed);
215 else
217 node->pei,
218 gm->initParam);
219
220 /* Try to launch workers. */
221 pcxt = node->pei->pcxt;
223 /* We save # workers launched for the benefit of EXPLAIN */
225
226 /*
227 * Count number of workers originally wanted and actually
228 * launched.
229 */
232
233 /* Set up tuple queue readers to read the results. */
234 if (pcxt->nworkers_launched > 0)
235 {
237 /* Make a working array showing the active readers */
238 node->nreaders = pcxt->nworkers_launched;
239 node->reader = (TupleQueueReader **)
240 palloc(node->nreaders * sizeof(TupleQueueReader *));
241 memcpy(node->reader, node->pei->reader,
242 node->nreaders * sizeof(TupleQueueReader *));
243 }
244 else
245 {
246 /* No workers? Then never mind. */
247 node->nreaders = 0;
248 node->reader = NULL;
249 }
250 }
251
252 /* allow leader to participate if enabled or no choice */
253 if (parallel_leader_participation || node->nreaders == 0)
254 node->need_to_scan_locally = true;
255 node->initialized = true;
256 }
257
258 /*
259 * Reset per-tuple memory context to free any expression evaluation
260 * storage allocated in the previous tuple cycle.
261 */
262 econtext = node->ps.ps_ExprContext;
263 ResetExprContext(econtext);
264
265 /*
266 * Get next tuple, either from one of our workers, or by running the plan
267 * ourselves.
268 */
269 slot = gather_merge_getnext(node);
270 if (TupIsNull(slot))
271 return NULL;
272
273 /* If no projection is required, we're done. */
274 if (node->ps.ps_ProjInfo == NULL)
275 return slot;
276
277 /*
278 * Form the result tuple using ExecProject(), and return it.
279 */
280 econtext->ecxt_outertuple = slot;
281 return ExecProject(node->ps.ps_ProjInfo);
282}
void LaunchParallelWorkers(ParallelContext *pcxt)
Definition: parallel.c:569
void ExecParallelReinitialize(PlanState *planstate, ParallelExecutorInfo *pei, Bitmapset *sendParams)
Definition: execParallel.c:904
void ExecParallelCreateReaders(ParallelExecutorInfo *pei)
Definition: execParallel.c:878
ParallelExecutorInfo * ExecInitParallelPlan(PlanState *planstate, EState *estate, Bitmapset *sendParams, int nworkers, int64 tuples_needed)
Definition: execParallel.c:587
static TupleTableSlot * ExecProject(ProjectionInfo *projInfo)
Definition: executor.h:389
#define ResetExprContext(econtext)
Definition: executor.h:557
void * palloc(Size size)
Definition: mcxt.c:1317
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:122
static TupleTableSlot * gather_merge_getnext(GatherMergeState *gm_state)
#define castNode(_type_, nodeptr)
Definition: nodes.h:176
bool parallel_leader_participation
Definition: planner.c:68
int es_parallel_workers_to_launch
Definition: execnodes.h:711
bool es_use_parallel_mode
Definition: execnodes.h:709
int es_parallel_workers_launched
Definition: execnodes.h:713
TupleTableSlot * ecxt_outertuple
Definition: execnodes.h:262
struct ParallelExecutorInfo * pei
Definition: execnodes.h:2737
struct TupleQueueReader ** reader
Definition: execnodes.h:2743
bool need_to_scan_locally
Definition: execnodes.h:2731
PlanState ps
Definition: execnodes.h:2728
Bitmapset * initParam
Definition: plannodes.h:1187
int num_workers
Definition: plannodes.h:1161
int nworkers_launched
Definition: parallel.h:37
int nworkers_to_launch
Definition: parallel.h:36
ParallelContext * pcxt
Definition: execParallel.h:27
struct TupleQueueReader ** reader
Definition: execParallel.h:37
Plan * plan
Definition: execnodes.h:1126
EState * state
Definition: execnodes.h:1128
ExprContext * ps_ExprContext
Definition: execnodes.h:1165
ProjectionInfo * ps_ProjInfo
Definition: execnodes.h:1166
#define TupIsNull(slot)
Definition: tuptable.h:306

References castNode, CHECK_FOR_INTERRUPTS, ExprContext::ecxt_outertuple, EState::es_parallel_workers_launched, EState::es_parallel_workers_to_launch, EState::es_use_parallel_mode, ExecInitParallelPlan(), ExecParallelCreateReaders(), ExecParallelReinitialize(), ExecProject(), gather_merge_getnext(), GatherMergeState::initialized, GatherMerge::initParam, LaunchParallelWorkers(), GatherMergeState::need_to_scan_locally, GatherMergeState::nreaders, GatherMerge::num_workers, ParallelContext::nworkers_launched, GatherMergeState::nworkers_launched, ParallelContext::nworkers_to_launch, outerPlanState, palloc(), parallel_leader_participation, ParallelExecutorInfo::pcxt, GatherMergeState::pei, PlanState::plan, GatherMergeState::ps, PlanState::ps_ExprContext, PlanState::ps_ProjInfo, ParallelExecutorInfo::reader, GatherMergeState::reader, ResetExprContext, PlanState::state, TupIsNull, and GatherMergeState::tuples_needed.

Referenced by ExecInitGatherMerge().

◆ ExecInitGatherMerge()

GatherMergeState * ExecInitGatherMerge ( GatherMerge node,
EState estate,
int  eflags 
)

Definition at line 67 of file nodeGatherMerge.c.

68{
69 GatherMergeState *gm_state;
70 Plan *outerNode;
71 TupleDesc tupDesc;
72
73 /* Gather merge node doesn't have innerPlan node. */
74 Assert(innerPlan(node) == NULL);
75
76 /*
77 * create state structure
78 */
79 gm_state = makeNode(GatherMergeState);
80 gm_state->ps.plan = (Plan *) node;
81 gm_state->ps.state = estate;
83
84 gm_state->initialized = false;
85 gm_state->gm_initialized = false;
86 gm_state->tuples_needed = -1;
87
88 /*
89 * Miscellaneous initialization
90 *
91 * create expression context for node
92 */
93 ExecAssignExprContext(estate, &gm_state->ps);
94
95 /*
96 * GatherMerge doesn't support checking a qual (it's always more efficient
97 * to do it in the child node).
98 */
99 Assert(!node->plan.qual);
100
101 /*
102 * now initialize outer plan
103 */
104 outerNode = outerPlan(node);
105 outerPlanState(gm_state) = ExecInitNode(outerNode, estate, eflags);
106
107 /*
108 * Leader may access ExecProcNode result directly (if
109 * need_to_scan_locally), or from workers via tuple queue. So we can't
110 * trivially rely on the slot type being fixed for expressions evaluated
111 * within this node.
112 */
113 gm_state->ps.outeropsset = true;
114 gm_state->ps.outeropsfixed = false;
115
116 /*
117 * Store the tuple descriptor into gather merge state, so we can use it
118 * while initializing the gather merge slots.
119 */
120 tupDesc = ExecGetResultType(outerPlanState(gm_state));
121 gm_state->tupDesc = tupDesc;
122
123 /*
124 * Initialize result type and projection.
125 */
126 ExecInitResultTypeTL(&gm_state->ps);
128
129 /*
130 * Without projections result slot type is not trivially known, see
131 * comment above.
132 */
133 if (gm_state->ps.ps_ProjInfo == NULL)
134 {
135 gm_state->ps.resultopsset = true;
136 gm_state->ps.resultopsfixed = false;
137 }
138
139 /*
140 * initialize sort-key information
141 */
142 if (node->numCols)
143 {
144 int i;
145
146 gm_state->gm_nkeys = node->numCols;
147 gm_state->gm_sortkeys =
148 palloc0(sizeof(SortSupportData) * node->numCols);
149
150 for (i = 0; i < node->numCols; i++)
151 {
152 SortSupport sortKey = gm_state->gm_sortkeys + i;
153
155 sortKey->ssup_collation = node->collations[i];
156 sortKey->ssup_nulls_first = node->nullsFirst[i];
157 sortKey->ssup_attno = node->sortColIdx[i];
158
159 /*
160 * We don't perform abbreviated key conversion here, for the same
161 * reasons that it isn't used in MergeAppend
162 */
163 sortKey->abbreviate = false;
164
165 PrepareSortSupportFromOrderingOp(node->sortOperators[i], sortKey);
166 }
167 }
168
169 /* Now allocate the workspace for gather merge */
170 gather_merge_setup(gm_state);
171
172 return gm_state;
173}
#define Assert(condition)
Definition: c.h:812
PlanState * ExecInitNode(Plan *node, EState *estate, int eflags)
Definition: execProcnode.c:142
void ExecInitResultTypeTL(PlanState *planstate)
Definition: execTuples.c:1942
TupleDesc ExecGetResultType(PlanState *planstate)
Definition: execUtils.c:495
void ExecAssignExprContext(EState *estate, PlanState *planstate)
Definition: execUtils.c:485
void ExecConditionalAssignProjectionInfo(PlanState *planstate, TupleDesc inputDesc, int varno)
Definition: execUtils.c:603
int i
Definition: isn.c:72
void * palloc0(Size size)
Definition: mcxt.c:1347
MemoryContext CurrentMemoryContext
Definition: mcxt.c:143
static void gather_merge_setup(GatherMergeState *gm_state)
static TupleTableSlot * ExecGatherMerge(PlanState *pstate)
#define makeNode(_type_)
Definition: nodes.h:155
#define innerPlan(node)
Definition: plannodes.h:182
#define outerPlan(node)
Definition: plannodes.h:183
#define OUTER_VAR
Definition: primnodes.h:237
void PrepareSortSupportFromOrderingOp(Oid orderingOp, SortSupport ssup)
Definition: sortsupport.c:134
TupleDesc tupDesc
Definition: execnodes.h:2734
SortSupport gm_sortkeys
Definition: execnodes.h:2736
bool outeropsset
Definition: execnodes.h:1209
bool resultopsset
Definition: execnodes.h:1211
bool outeropsfixed
Definition: execnodes.h:1205
bool resultopsfixed
Definition: execnodes.h:1207
ExecProcNodeMtd ExecProcNode
Definition: execnodes.h:1132
List * qual
Definition: plannodes.h:154
AttrNumber ssup_attno
Definition: sortsupport.h:81
bool ssup_nulls_first
Definition: sortsupport.h:75
MemoryContext ssup_cxt
Definition: sortsupport.h:66

References SortSupportData::abbreviate, Assert, CurrentMemoryContext, ExecAssignExprContext(), ExecConditionalAssignProjectionInfo(), ExecGatherMerge(), ExecGetResultType(), ExecInitNode(), ExecInitResultTypeTL(), PlanState::ExecProcNode, gather_merge_setup(), GatherMergeState::gm_initialized, GatherMergeState::gm_nkeys, GatherMergeState::gm_sortkeys, i, GatherMergeState::initialized, innerPlan, makeNode, GatherMerge::numCols, OUTER_VAR, PlanState::outeropsfixed, PlanState::outeropsset, outerPlan, outerPlanState, palloc0(), PlanState::plan, GatherMerge::plan, PrepareSortSupportFromOrderingOp(), GatherMergeState::ps, PlanState::ps_ProjInfo, Plan::qual, PlanState::resultopsfixed, PlanState::resultopsset, SortSupportData::ssup_attno, SortSupportData::ssup_collation, SortSupportData::ssup_cxt, SortSupportData::ssup_nulls_first, PlanState::state, GatherMergeState::tupDesc, and GatherMergeState::tuples_needed.

Referenced by ExecInitNode().

◆ ExecReScanGatherMerge()

void ExecReScanGatherMerge ( GatherMergeState node)

Definition at line 341 of file nodeGatherMerge.c.

342{
343 GatherMerge *gm = (GatherMerge *) node->ps.plan;
345
346 /* Make sure any existing workers are gracefully shut down */
348
349 /* Free any unused tuples, so we don't leak memory across rescans */
351
352 /* Mark node so that shared state will be rebuilt at next call */
353 node->initialized = false;
354 node->gm_initialized = false;
355
356 /*
357 * Set child node's chgParam to tell it that the next scan might deliver a
358 * different set of rows within the leader process. (The overall rowset
359 * shouldn't change, but the leader process's subset might; hence nodes
360 * between here and the parallel table scan node mustn't optimize on the
361 * assumption of an unchanging rowset.)
362 */
363 if (gm->rescan_param >= 0)
364 outerPlan->chgParam = bms_add_member(outerPlan->chgParam,
365 gm->rescan_param);
366
367 /*
368 * If chgParam of subnode is not null then plan will be re-scanned by
369 * first ExecProcNode. Note: because this does nothing if we have a
370 * rescan_param, it's currently guaranteed that parallel-aware child nodes
371 * will not see a ReScan call until after they get a ReInitializeDSM call.
372 * That ordering might not be something to rely on, though. A good rule
373 * of thumb is that ReInitializeDSM should reset only shared state, ReScan
374 * should reset only local state, and anything that depends on both of
375 * those steps being finished must wait until the first ExecProcNode call.
376 */
377 if (outerPlan->chgParam == NULL)
379}
Bitmapset * bms_add_member(Bitmapset *a, int x)
Definition: bitmapset.c:815
void ExecReScan(PlanState *node)
Definition: execAmi.c:76
static void gather_merge_clear_tuples(GatherMergeState *gm_state)
static void ExecShutdownGatherMergeWorkers(GatherMergeState *node)
int rescan_param
Definition: plannodes.h:1164

References bms_add_member(), ExecReScan(), ExecShutdownGatherMergeWorkers(), gather_merge_clear_tuples(), GatherMergeState::gm_initialized, GatherMergeState::initialized, outerPlan, outerPlanState, PlanState::plan, GatherMergeState::ps, and GatherMerge::rescan_param.

Referenced by ExecReScan().

◆ ExecShutdownGatherMerge()

void ExecShutdownGatherMerge ( GatherMergeState node)

Definition at line 304 of file nodeGatherMerge.c.

305{
307
308 /* Now destroy the parallel context. */
309 if (node->pei != NULL)
310 {
312 node->pei = NULL;
313 }
314}
void ExecParallelCleanup(ParallelExecutorInfo *pei)

References ExecParallelCleanup(), ExecShutdownGatherMergeWorkers(), and GatherMergeState::pei.

Referenced by ExecEndGatherMerge(), and ExecShutdownNode_walker().

◆ ExecShutdownGatherMergeWorkers()

static void ExecShutdownGatherMergeWorkers ( GatherMergeState node)
static

Definition at line 323 of file nodeGatherMerge.c.

324{
325 if (node->pei != NULL)
326 ExecParallelFinish(node->pei);
327
328 /* Flush local copy of reader array */
329 if (node->reader)
330 pfree(node->reader);
331 node->reader = NULL;
332}
void ExecParallelFinish(ParallelExecutorInfo *pei)
void pfree(void *pointer)
Definition: mcxt.c:1521

References ExecParallelFinish(), GatherMergeState::pei, pfree(), and GatherMergeState::reader.

Referenced by ExecReScanGatherMerge(), and ExecShutdownGatherMerge().

◆ gather_merge_clear_tuples()

static void gather_merge_clear_tuples ( GatherMergeState gm_state)
static

Definition at line 526 of file nodeGatherMerge.c.

527{
528 int i;
529
530 for (i = 0; i < gm_state->nreaders; i++)
531 {
532 GMReaderTupleBuffer *tuple_buffer = &gm_state->gm_tuple_buffers[i];
533
534 while (tuple_buffer->readCounter < tuple_buffer->nTuples)
535 pfree(tuple_buffer->tuple[tuple_buffer->readCounter++]);
536
537 ExecClearTuple(gm_state->gm_slots[i + 1]);
538 }
539}
MinimalTuple * tuple
struct GMReaderTupleBuffer * gm_tuple_buffers
Definition: execnodes.h:2744
TupleTableSlot ** gm_slots
Definition: execnodes.h:2742
static TupleTableSlot * ExecClearTuple(TupleTableSlot *slot)
Definition: tuptable.h:454

References ExecClearTuple(), GatherMergeState::gm_slots, GatherMergeState::gm_tuple_buffers, i, GatherMergeState::nreaders, GMReaderTupleBuffer::nTuples, pfree(), GMReaderTupleBuffer::readCounter, and GMReaderTupleBuffer::tuple.

Referenced by ExecReScanGatherMerge(), and gather_merge_getnext().

◆ gather_merge_getnext()

static TupleTableSlot * gather_merge_getnext ( GatherMergeState gm_state)
static

Definition at line 547 of file nodeGatherMerge.c.

548{
549 int i;
550
551 if (!gm_state->gm_initialized)
552 {
553 /*
554 * First time through: pull the first tuple from each participant, and
555 * set up the heap.
556 */
557 gather_merge_init(gm_state);
558 }
559 else
560 {
561 /*
562 * Otherwise, pull the next tuple from whichever participant we
563 * returned from last time, and reinsert that participant's index into
564 * the heap, because it might now compare differently against the
565 * other elements of the heap.
566 */
568
569 if (gather_merge_readnext(gm_state, i, false))
571 else
572 {
573 /* reader exhausted, remove it from heap */
574 (void) binaryheap_remove_first(gm_state->gm_heap);
575 }
576 }
577
578 if (binaryheap_empty(gm_state->gm_heap))
579 {
580 /* All the queues are exhausted, and so is the heap */
582 return NULL;
583 }
584 else
585 {
586 /* Return next tuple from whichever participant has the leading one */
588 return gm_state->gm_slots[i];
589 }
590}
void binaryheap_replace_first(binaryheap *heap, bh_node_type d)
Definition: binaryheap.c:255
bh_node_type binaryheap_first(binaryheap *heap)
Definition: binaryheap.c:177
bh_node_type binaryheap_remove_first(binaryheap *heap)
Definition: binaryheap.c:192
#define binaryheap_empty(h)
Definition: binaryheap.h:65
static void gather_merge_init(GatherMergeState *gm_state)
static bool gather_merge_readnext(GatherMergeState *gm_state, int reader, bool nowait)
static Datum Int32GetDatum(int32 X)
Definition: postgres.h:212
static int32 DatumGetInt32(Datum X)
Definition: postgres.h:202
struct binaryheap * gm_heap
Definition: execnodes.h:2745

References binaryheap_empty, binaryheap_first(), binaryheap_remove_first(), binaryheap_replace_first(), DatumGetInt32(), gather_merge_clear_tuples(), gather_merge_init(), gather_merge_readnext(), GatherMergeState::gm_heap, GatherMergeState::gm_initialized, GatherMergeState::gm_slots, i, and Int32GetDatum().

Referenced by ExecGatherMerge().

◆ gather_merge_init()

static void gather_merge_init ( GatherMergeState gm_state)
static

Definition at line 443 of file nodeGatherMerge.c.

444{
445 int nreaders = gm_state->nreaders;
446 bool nowait = true;
447 int i;
448
449 /* Assert that gather_merge_setup made enough space */
450 Assert(nreaders <= castNode(GatherMerge, gm_state->ps.plan)->num_workers);
451
452 /* Reset leader's tuple slot to empty */
453 gm_state->gm_slots[0] = NULL;
454
455 /* Reset the tuple slot and tuple array for each worker */
456 for (i = 0; i < nreaders; i++)
457 {
458 /* Reset tuple array to empty */
459 gm_state->gm_tuple_buffers[i].nTuples = 0;
460 gm_state->gm_tuple_buffers[i].readCounter = 0;
461 /* Reset done flag to not-done */
462 gm_state->gm_tuple_buffers[i].done = false;
463 /* Ensure output slot is empty */
464 ExecClearTuple(gm_state->gm_slots[i + 1]);
465 }
466
467 /* Reset binary heap to empty */
468 binaryheap_reset(gm_state->gm_heap);
469
470 /*
471 * First, try to read a tuple from each worker (including leader) in
472 * nowait mode. After this, if not all workers were able to produce a
473 * tuple (or a "done" indication), then re-read from remaining workers,
474 * this time using wait mode. Add all live readers (those producing at
475 * least one tuple) to the heap.
476 */
477reread:
478 for (i = 0; i <= nreaders; i++)
479 {
481
482 /* skip this source if already known done */
483 if ((i == 0) ? gm_state->need_to_scan_locally :
484 !gm_state->gm_tuple_buffers[i - 1].done)
485 {
486 if (TupIsNull(gm_state->gm_slots[i]))
487 {
488 /* Don't have a tuple yet, try to get one */
489 if (gather_merge_readnext(gm_state, i, nowait))
492 }
493 else
494 {
495 /*
496 * We already got at least one tuple from this worker, but
497 * might as well see if it has any more ready by now.
498 */
499 load_tuple_array(gm_state, i);
500 }
501 }
502 }
503
504 /* need not recheck leader, since nowait doesn't matter for it */
505 for (i = 1; i <= nreaders; i++)
506 {
507 if (!gm_state->gm_tuple_buffers[i - 1].done &&
508 TupIsNull(gm_state->gm_slots[i]))
509 {
510 nowait = false;
511 goto reread;
512 }
513 }
514
515 /* Now heapify the heap. */
516 binaryheap_build(gm_state->gm_heap);
517
518 gm_state->gm_initialized = true;
519}
void binaryheap_build(binaryheap *heap)
Definition: binaryheap.c:138
void binaryheap_reset(binaryheap *heap)
Definition: binaryheap.c:63
void binaryheap_add_unordered(binaryheap *heap, bh_node_type d)
Definition: binaryheap.c:116
static void load_tuple_array(GatherMergeState *gm_state, int reader)

References Assert, binaryheap_add_unordered(), binaryheap_build(), binaryheap_reset(), castNode, CHECK_FOR_INTERRUPTS, GMReaderTupleBuffer::done, ExecClearTuple(), gather_merge_readnext(), GatherMergeState::gm_heap, GatherMergeState::gm_initialized, GatherMergeState::gm_slots, GatherMergeState::gm_tuple_buffers, i, Int32GetDatum(), load_tuple_array(), GatherMergeState::need_to_scan_locally, GatherMergeState::nreaders, GMReaderTupleBuffer::nTuples, PlanState::plan, GatherMergeState::ps, GMReaderTupleBuffer::readCounter, and TupIsNull.

Referenced by gather_merge_getnext().

◆ gather_merge_readnext()

static bool gather_merge_readnext ( GatherMergeState gm_state,
int  reader,
bool  nowait 
)
static

Definition at line 636 of file nodeGatherMerge.c.

637{
638 GMReaderTupleBuffer *tuple_buffer;
639 MinimalTuple tup;
640
641 /*
642 * If we're being asked to generate a tuple from the leader, then we just
643 * call ExecProcNode as normal to produce one.
644 */
645 if (reader == 0)
646 {
647 if (gm_state->need_to_scan_locally)
648 {
650 TupleTableSlot *outerTupleSlot;
651 EState *estate = gm_state->ps.state;
652
653 /* Install our DSA area while executing the plan. */
654 estate->es_query_dsa = gm_state->pei ? gm_state->pei->area : NULL;
655 outerTupleSlot = ExecProcNode(outerPlan);
656 estate->es_query_dsa = NULL;
657
658 if (!TupIsNull(outerTupleSlot))
659 {
660 gm_state->gm_slots[0] = outerTupleSlot;
661 return true;
662 }
663 /* need_to_scan_locally serves as "done" flag for leader */
664 gm_state->need_to_scan_locally = false;
665 }
666 return false;
667 }
668
669 /* Otherwise, check the state of the relevant tuple buffer. */
670 tuple_buffer = &gm_state->gm_tuple_buffers[reader - 1];
671
672 if (tuple_buffer->nTuples > tuple_buffer->readCounter)
673 {
674 /* Return any tuple previously read that is still buffered. */
675 tup = tuple_buffer->tuple[tuple_buffer->readCounter++];
676 }
677 else if (tuple_buffer->done)
678 {
679 /* Reader is known to be exhausted. */
680 return false;
681 }
682 else
683 {
684 /* Read and buffer next tuple. */
685 tup = gm_readnext_tuple(gm_state,
686 reader,
687 nowait,
688 &tuple_buffer->done);
689 if (!tup)
690 return false;
691
692 /*
693 * Attempt to read more tuples in nowait mode and store them in the
694 * pending-tuple array for the reader.
695 */
696 load_tuple_array(gm_state, reader);
697 }
698
699 Assert(tup);
700
701 /* Build the TupleTableSlot for the given tuple */
702 ExecStoreMinimalTuple(tup, /* tuple to store */
703 gm_state->gm_slots[reader], /* slot in which to
704 * store the tuple */
705 true); /* pfree tuple when done with it */
706
707 return true;
708}
TupleTableSlot * ExecStoreMinimalTuple(MinimalTuple mtup, TupleTableSlot *slot, bool shouldFree)
Definition: execTuples.c:1633
static TupleTableSlot * ExecProcNode(PlanState *node)
Definition: executor.h:267
static MinimalTuple gm_readnext_tuple(GatherMergeState *gm_state, int nreader, bool nowait, bool *done)
struct dsa_area * es_query_dsa
Definition: execnodes.h:717

References ParallelExecutorInfo::area, Assert, GMReaderTupleBuffer::done, EState::es_query_dsa, ExecProcNode(), ExecStoreMinimalTuple(), gm_readnext_tuple(), GatherMergeState::gm_slots, GatherMergeState::gm_tuple_buffers, load_tuple_array(), GatherMergeState::need_to_scan_locally, GMReaderTupleBuffer::nTuples, outerPlan, outerPlanState, GatherMergeState::pei, GatherMergeState::ps, GMReaderTupleBuffer::readCounter, PlanState::state, TupIsNull, and GMReaderTupleBuffer::tuple.

Referenced by gather_merge_getnext(), and gather_merge_init().

◆ gather_merge_setup()

static void gather_merge_setup ( GatherMergeState gm_state)
static

Definition at line 395 of file nodeGatherMerge.c.

396{
397 GatherMerge *gm = castNode(GatherMerge, gm_state->ps.plan);
398 int nreaders = gm->num_workers;
399 int i;
400
401 /*
402 * Allocate gm_slots for the number of workers + one more slot for leader.
403 * Slot 0 is always for the leader. Leader always calls ExecProcNode() to
404 * read the tuple, and then stores it directly into its gm_slots entry.
405 * For other slots, code below will call ExecInitExtraTupleSlot() to
406 * create a slot for the worker's results. Note that during any single
407 * scan, we might have fewer than num_workers available workers, in which
408 * case the extra array entries go unused.
409 */
410 gm_state->gm_slots = (TupleTableSlot **)
411 palloc0((nreaders + 1) * sizeof(TupleTableSlot *));
412
413 /* Allocate the tuple slot and tuple array for each worker */
415 palloc0(nreaders * sizeof(GMReaderTupleBuffer));
416
417 for (i = 0; i < nreaders; i++)
418 {
419 /* Allocate the tuple array with length MAX_TUPLE_STORE */
420 gm_state->gm_tuple_buffers[i].tuple =
422
423 /* Initialize tuple slot for worker */
424 gm_state->gm_slots[i + 1] =
425 ExecInitExtraTupleSlot(gm_state->ps.state, gm_state->tupDesc,
427 }
428
429 /* Allocate the resources for the merge */
430 gm_state->gm_heap = binaryheap_allocate(nreaders + 1,
432 gm_state);
433}
binaryheap * binaryheap_allocate(int capacity, binaryheap_comparator compare, void *arg)
Definition: binaryheap.c:39
TupleTableSlot * ExecInitExtraTupleSlot(EState *estate, TupleDesc tupledesc, const TupleTableSlotOps *tts_ops)
Definition: execTuples.c:2018
const TupleTableSlotOps TTSOpsMinimalTuple
Definition: execTuples.c:86
static int32 heap_compare_slots(Datum a, Datum b, void *arg)
#define MAX_TUPLE_STORE

References binaryheap_allocate(), castNode, ExecInitExtraTupleSlot(), GatherMergeState::gm_heap, GatherMergeState::gm_slots, GatherMergeState::gm_tuple_buffers, heap_compare_slots(), i, MAX_TUPLE_STORE, GatherMerge::num_workers, palloc0(), PlanState::plan, GatherMergeState::ps, PlanState::state, TTSOpsMinimalTuple, GatherMergeState::tupDesc, and GMReaderTupleBuffer::tuple.

Referenced by ExecInitGatherMerge().

◆ gm_readnext_tuple()

static MinimalTuple gm_readnext_tuple ( GatherMergeState gm_state,
int  nreader,
bool  nowait,
bool *  done 
)
static

Definition at line 714 of file nodeGatherMerge.c.

716{
717 TupleQueueReader *reader;
718 MinimalTuple tup;
719
720 /* Check for async events, particularly messages from workers. */
722
723 /*
724 * Attempt to read a tuple.
725 *
726 * Note that TupleQueueReaderNext will just return NULL for a worker which
727 * fails to initialize. We'll treat that worker as having produced no
728 * tuples; WaitForParallelWorkersToFinish will error out when we get
729 * there.
730 */
731 reader = gm_state->reader[nreader - 1];
732 tup = TupleQueueReaderNext(reader, nowait, done);
733
734 /*
735 * Since we'll be buffering these across multiple calls, we need to make a
736 * copy.
737 */
738 return tup ? heap_copy_minimal_tuple(tup) : NULL;
739}
MinimalTuple heap_copy_minimal_tuple(MinimalTuple mtup)
Definition: heaptuple.c:1536
MinimalTuple TupleQueueReaderNext(TupleQueueReader *reader, bool nowait, bool *done)
Definition: tqueue.c:176

References CHECK_FOR_INTERRUPTS, heap_copy_minimal_tuple(), GatherMergeState::reader, and TupleQueueReaderNext().

Referenced by gather_merge_readnext(), and load_tuple_array().

◆ heap_compare_slots()

static int32 heap_compare_slots ( Datum  a,
Datum  b,
void *  arg 
)
static

Definition at line 752 of file nodeGatherMerge.c.

753{
755 SlotNumber slot1 = DatumGetInt32(a);
756 SlotNumber slot2 = DatumGetInt32(b);
757
758 TupleTableSlot *s1 = node->gm_slots[slot1];
759 TupleTableSlot *s2 = node->gm_slots[slot2];
760 int nkey;
761
764
765 for (nkey = 0; nkey < node->gm_nkeys; nkey++)
766 {
767 SortSupport sortKey = node->gm_sortkeys + nkey;
768 AttrNumber attno = sortKey->ssup_attno;
769 Datum datum1,
770 datum2;
771 bool isNull1,
772 isNull2;
773 int compare;
774
775 datum1 = slot_getattr(s1, attno, &isNull1);
776 datum2 = slot_getattr(s2, attno, &isNull2);
777
778 compare = ApplySortComparator(datum1, isNull1,
779 datum2, isNull2,
780 sortKey);
781 if (compare != 0)
782 {
784 return compare;
785 }
786 }
787 return 0;
788}
int16 AttrNumber
Definition: attnum.h:21
#define INVERT_COMPARE_RESULT(var)
Definition: c.h:1060
static int compare(const void *arg1, const void *arg2)
Definition: geqo_pool.c:145
int b
Definition: isn.c:69
int a
Definition: isn.c:68
int32 SlotNumber
void * arg
uintptr_t Datum
Definition: postgres.h:64
char * s1
char * s2
static int ApplySortComparator(Datum datum1, bool isNull1, Datum datum2, bool isNull2, SortSupport ssup)
Definition: sortsupport.h:200
static Datum slot_getattr(TupleTableSlot *slot, int attnum, bool *isnull)
Definition: tuptable.h:395

References a, ApplySortComparator(), arg, Assert, b, compare(), DatumGetInt32(), GatherMergeState::gm_nkeys, GatherMergeState::gm_slots, GatherMergeState::gm_sortkeys, INVERT_COMPARE_RESULT, s1, s2, slot_getattr(), SortSupportData::ssup_attno, and TupIsNull.

Referenced by gather_merge_setup().

◆ load_tuple_array()

static void load_tuple_array ( GatherMergeState gm_state,
int  reader 
)
static

Definition at line 597 of file nodeGatherMerge.c.

598{
599 GMReaderTupleBuffer *tuple_buffer;
600 int i;
601
602 /* Don't do anything if this is the leader. */
603 if (reader == 0)
604 return;
605
606 tuple_buffer = &gm_state->gm_tuple_buffers[reader - 1];
607
608 /* If there's nothing in the array, reset the counters to zero. */
609 if (tuple_buffer->nTuples == tuple_buffer->readCounter)
610 tuple_buffer->nTuples = tuple_buffer->readCounter = 0;
611
612 /* Try to fill additional slots in the array. */
613 for (i = tuple_buffer->nTuples; i < MAX_TUPLE_STORE; i++)
614 {
615 MinimalTuple tuple;
616
617 tuple = gm_readnext_tuple(gm_state,
618 reader,
619 true,
620 &tuple_buffer->done);
621 if (!tuple)
622 break;
623 tuple_buffer->tuple[i] = tuple;
624 tuple_buffer->nTuples++;
625 }
626}

References GMReaderTupleBuffer::done, gm_readnext_tuple(), GatherMergeState::gm_tuple_buffers, i, MAX_TUPLE_STORE, GMReaderTupleBuffer::nTuples, GMReaderTupleBuffer::readCounter, and GMReaderTupleBuffer::tuple.

Referenced by gather_merge_init(), and gather_merge_readnext().