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nodeGather.h File Reference
#include "nodes/execnodes.h"
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Functions

GatherStateExecInitGather (Gather *node, EState *estate, int eflags)
 
TupleTableSlotExecGather (GatherState *node)
 
void ExecEndGather (GatherState *node)
 
void ExecShutdownGather (GatherState *node)
 
void ExecReScanGather (GatherState *node)
 

Function Documentation

void ExecEndGather ( GatherState node)

Definition at line 230 of file nodeGather.c.

References ExecClearTuple(), ExecEndNode(), ExecFreeExprContext(), ExecShutdownGather(), outerPlanState, GatherState::ps, and PlanState::ps_ResultTupleSlot.

Referenced by ExecEndNode().

231 {
232  ExecEndNode(outerPlanState(node)); /* let children clean up first */
233  ExecShutdownGather(node);
234  ExecFreeExprContext(&node->ps);
236 }
void ExecEndNode(PlanState *node)
Definition: execProcnode.c:624
TupleTableSlot * ExecClearTuple(TupleTableSlot *slot)
Definition: execTuples.c:439
void ExecFreeExprContext(PlanState *planstate)
Definition: execUtils.c:685
TupleTableSlot * ps_ResultTupleSlot
Definition: execnodes.h:1077
#define outerPlanState(node)
Definition: execnodes.h:1090
PlanState ps
Definition: execnodes.h:2004
void ExecShutdownGather(GatherState *node)
Definition: nodeGather.c:404
TupleTableSlot* ExecGather ( GatherState node)

Definition at line 128 of file nodeGather.c.

References ParallelWorkerInfo::bgwhandle, CreateTupleQueueReader(), ExprContext::ecxt_outertuple, ExecClearTuple(), ExecInitParallelPlan(), ExecProject(), ExecShutdownGatherWorkers(), GatherState::funnel_slot, gather_getnext(), i, GatherState::initialized, IsInParallelMode(), LaunchParallelWorkers(), PlanState::lefttree, GatherState::need_to_scan_locally, GatherState::nextreader, GatherState::nreaders, NULL, Gather::num_workers, ParallelContext::nworkers_launched, GatherState::nworkers_launched, palloc(), ParallelExecutorInfo::pcxt, GatherState::pei, PlanState::plan, GatherState::ps, PlanState::ps_ExprContext, PlanState::ps_ProjInfo, GatherState::reader, ResetExprContext, shm_mq_set_handle(), Gather::single_copy, PlanState::state, ParallelExecutorInfo::tqueue, TupleTableSlot::tts_tupleDescriptor, TupIsNull, and ParallelContext::worker.

Referenced by ExecProcNode().

129 {
130  TupleTableSlot *fslot = node->funnel_slot;
131  int i;
132  TupleTableSlot *slot;
133  ExprContext *econtext;
134 
135  /*
136  * Initialize the parallel context and workers on first execution. We do
137  * this on first execution rather than during node initialization, as it
138  * needs to allocate a large dynamic segment, so it is better to do it
139  * only if it is really needed.
140  */
141  if (!node->initialized)
142  {
143  EState *estate = node->ps.state;
144  Gather *gather = (Gather *) node->ps.plan;
145 
146  /*
147  * Sometimes we might have to run without parallelism; but if parallel
148  * mode is active then we can try to fire up some workers.
149  */
150  if (gather->num_workers > 0 && IsInParallelMode())
151  {
152  ParallelContext *pcxt;
153 
154  /* Initialize the workers required to execute Gather node. */
155  if (!node->pei)
156  node->pei = ExecInitParallelPlan(node->ps.lefttree,
157  estate,
158  gather->num_workers);
159 
160  /*
161  * Register backend workers. We might not get as many as we
162  * requested, or indeed any at all.
163  */
164  pcxt = node->pei->pcxt;
165  LaunchParallelWorkers(pcxt);
166  node->nworkers_launched = pcxt->nworkers_launched;
167 
168  /* Set up tuple queue readers to read the results. */
169  if (pcxt->nworkers_launched > 0)
170  {
171  node->nreaders = 0;
172  node->nextreader = 0;
173  node->reader =
174  palloc(pcxt->nworkers_launched * sizeof(TupleQueueReader *));
175 
176  for (i = 0; i < pcxt->nworkers_launched; ++i)
177  {
178  shm_mq_set_handle(node->pei->tqueue[i],
179  pcxt->worker[i].bgwhandle);
180  node->reader[node->nreaders++] =
182  fslot->tts_tupleDescriptor);
183  }
184  }
185  else
186  {
187  /* No workers? Then never mind. */
189  }
190  }
191 
192  /* Run plan locally if no workers or not single-copy. */
193  node->need_to_scan_locally = (node->reader == NULL)
194  || !gather->single_copy;
195  node->initialized = true;
196  }
197 
198  /*
199  * Reset per-tuple memory context to free any expression evaluation
200  * storage allocated in the previous tuple cycle. This will also clear
201  * any previous tuple returned by a TupleQueueReader; to make sure we
202  * don't leave a dangling pointer around, clear the working slot first.
203  */
204  ExecClearTuple(fslot);
205  econtext = node->ps.ps_ExprContext;
206  ResetExprContext(econtext);
207 
208  /*
209  * Get next tuple, either from one of our workers, or by running the plan
210  * ourselves.
211  */
212  slot = gather_getnext(node);
213  if (TupIsNull(slot))
214  return NULL;
215 
216  /*
217  * Form the result tuple using ExecProject(), and return it.
218  */
219  econtext->ecxt_outertuple = slot;
220  return ExecProject(node->ps.ps_ProjInfo);
221 }
TupleTableSlot * ExecProject(ProjectionInfo *projInfo)
Definition: execQual.c:5214
ParallelContext * pcxt
Definition: execParallel.h:27
int nworkers_launched
Definition: execnodes.h:2009
ProjectionInfo * ps_ProjInfo
Definition: execnodes.h:1079
ExprContext * ps_ExprContext
Definition: execnodes.h:1078
TupleTableSlot * ExecClearTuple(TupleTableSlot *slot)
Definition: execTuples.c:439
bool need_to_scan_locally
Definition: execnodes.h:2012
struct TupleQueueReader ** reader
Definition: execnodes.h:2010
ParallelExecutorInfo * ExecInitParallelPlan(PlanState *planstate, EState *estate, int nworkers)
Definition: execParallel.c:357
EState * state
Definition: execnodes.h:1049
struct PlanState * lefttree
Definition: execnodes.h:1063
ParallelWorkerInfo * worker
Definition: parallel.h:46
bool IsInParallelMode(void)
Definition: xact.c:912
bool initialized
Definition: execnodes.h:2005
static void ExecShutdownGatherWorkers(GatherState *node)
Definition: nodeGather.c:376
bool single_copy
Definition: plannodes.h:784
struct ParallelExecutorInfo * pei
Definition: execnodes.h:2006
BackgroundWorkerHandle * bgwhandle
Definition: parallel.h:27
#define TupIsNull(slot)
Definition: tuptable.h:138
PlanState ps
Definition: execnodes.h:2004
int nworkers_launched
Definition: parallel.h:37
void LaunchParallelWorkers(ParallelContext *pcxt)
Definition: parallel.c:433
TupleDesc tts_tupleDescriptor
Definition: tuptable.h:121
TupleTableSlot * funnel_slot
Definition: execnodes.h:2011
void shm_mq_set_handle(shm_mq_handle *mqh, BackgroundWorkerHandle *handle)
Definition: shm_mq.c:311
Plan * plan
Definition: execnodes.h:1047
int num_workers
Definition: plannodes.h:783
TupleTableSlot * ecxt_outertuple
Definition: execnodes.h:130
#define NULL
Definition: c.h:226
static TupleTableSlot * gather_getnext(GatherState *gatherstate)
Definition: nodeGather.c:244
int nextreader
Definition: execnodes.h:2008
void * palloc(Size size)
Definition: mcxt.c:891
int i
TupleQueueReader * CreateTupleQueueReader(shm_mq_handle *handle, TupleDesc tupledesc)
Definition: tqueue.c:633
shm_mq_handle ** tqueue
Definition: execParallel.h:30
#define ResetExprContext(econtext)
Definition: executor.h:332
GatherState* ExecInitGather ( Gather node,
EState estate,
int  eflags 
)

Definition at line 56 of file nodeGather.c.

References Assert, ExecAssignExprContext(), ExecAssignProjectionInfo(), ExecAssignResultTypeFromTL(), ExecContextForcesOids(), ExecInitExpr(), ExecInitExtraTupleSlot(), ExecInitNode(), ExecInitResultTupleSlot(), ExecSetSlotDescriptor(), ExecTypeFromTL(), GatherState::funnel_slot, innerPlan, makeNode, GatherState::need_to_scan_locally, NULL, outerPlan, outerPlanState, Gather::plan, PlanState::plan, GatherState::ps, Plan::qual, PlanState::qual, Gather::single_copy, PlanState::state, Plan::targetlist, and PlanState::targetlist.

Referenced by ExecInitNode().

57 {
58  GatherState *gatherstate;
59  Plan *outerNode;
60  bool hasoid;
61  TupleDesc tupDesc;
62 
63  /* Gather node doesn't have innerPlan node. */
64  Assert(innerPlan(node) == NULL);
65 
66  /*
67  * create state structure
68  */
69  gatherstate = makeNode(GatherState);
70  gatherstate->ps.plan = (Plan *) node;
71  gatherstate->ps.state = estate;
72  gatherstate->need_to_scan_locally = !node->single_copy;
73 
74  /*
75  * Miscellaneous initialization
76  *
77  * create expression context for node
78  */
79  ExecAssignExprContext(estate, &gatherstate->ps);
80 
81  /*
82  * initialize child expressions
83  */
84  gatherstate->ps.targetlist = (List *)
85  ExecInitExpr((Expr *) node->plan.targetlist,
86  (PlanState *) gatherstate);
87  gatherstate->ps.qual = (List *)
88  ExecInitExpr((Expr *) node->plan.qual,
89  (PlanState *) gatherstate);
90 
91  /*
92  * tuple table initialization
93  */
94  gatherstate->funnel_slot = ExecInitExtraTupleSlot(estate);
95  ExecInitResultTupleSlot(estate, &gatherstate->ps);
96 
97  /*
98  * now initialize outer plan
99  */
100  outerNode = outerPlan(node);
101  outerPlanState(gatherstate) = ExecInitNode(outerNode, estate, eflags);
102 
103  /*
104  * Initialize result tuple type and projection info.
105  */
106  ExecAssignResultTypeFromTL(&gatherstate->ps);
107  ExecAssignProjectionInfo(&gatherstate->ps, NULL);
108 
109  /*
110  * Initialize funnel slot to same tuple descriptor as outer plan.
111  */
112  if (!ExecContextForcesOids(&gatherstate->ps, &hasoid))
113  hasoid = false;
114  tupDesc = ExecTypeFromTL(outerNode->targetlist, hasoid);
115  ExecSetSlotDescriptor(gatherstate->funnel_slot, tupDesc);
116 
117  return gatherstate;
118 }
List * qual
Definition: plannodes.h:130
TupleTableSlot * ExecInitExtraTupleSlot(EState *estate)
Definition: execTuples.c:852
List * qual
Definition: execnodes.h:1062
bool need_to_scan_locally
Definition: execnodes.h:2012
List * targetlist
Definition: execnodes.h:1061
EState * state
Definition: execnodes.h:1049
void ExecAssignResultTypeFromTL(PlanState *planstate)
Definition: execUtils.c:430
ExprState * ExecInitExpr(Expr *node, PlanState *parent)
Definition: execQual.c:4266
Plan plan
Definition: plannodes.h:782
bool single_copy
Definition: plannodes.h:784
void ExecInitResultTupleSlot(EState *estate, PlanState *planstate)
Definition: execTuples.c:832
#define outerPlanState(node)
Definition: execnodes.h:1090
#define innerPlan(node)
Definition: plannodes.h:158
void ExecAssignProjectionInfo(PlanState *planstate, TupleDesc inputDesc)
Definition: execUtils.c:657
PlanState ps
Definition: execnodes.h:2004
TupleDesc ExecTypeFromTL(List *targetList, bool hasoid)
Definition: execTuples.c:888
#define outerPlan(node)
Definition: plannodes.h:159
void ExecSetSlotDescriptor(TupleTableSlot *slot, TupleDesc tupdesc)
Definition: execTuples.c:247
TupleTableSlot * funnel_slot
Definition: execnodes.h:2011
Plan * plan
Definition: execnodes.h:1047
#define makeNode(_type_)
Definition: nodes.h:557
#define NULL
Definition: c.h:226
#define Assert(condition)
Definition: c.h:671
void ExecAssignExprContext(EState *estate, PlanState *planstate)
Definition: execUtils.c:408
List * targetlist
Definition: plannodes.h:129
bool ExecContextForcesOids(PlanState *planstate, bool *hasoids)
Definition: execMain.c:1406
PlanState * ExecInitNode(Plan *node, EState *estate, int eflags)
Definition: execProcnode.c:137
Definition: pg_list.h:45
void ExecReScanGather ( GatherState node)

Definition at line 428 of file nodeGather.c.

References ExecParallelReinitialize(), ExecReScan(), ExecShutdownGatherWorkers(), GatherState::initialized, PlanState::lefttree, GatherState::pei, and GatherState::ps.

Referenced by ExecReScan().

429 {
430  /*
431  * Re-initialize the parallel workers to perform rescan of relation. We
432  * want to gracefully shutdown all the workers so that they should be able
433  * to propagate any error or other information to master backend before
434  * dying. Parallel context will be reused for rescan.
435  */
437 
438  node->initialized = false;
439 
440  if (node->pei)
442 
443  ExecReScan(node->ps.lefttree);
444 }
void ExecReScan(PlanState *node)
Definition: execAmi.c:73
struct PlanState * lefttree
Definition: execnodes.h:1063
bool initialized
Definition: execnodes.h:2005
static void ExecShutdownGatherWorkers(GatherState *node)
Definition: nodeGather.c:376
struct ParallelExecutorInfo * pei
Definition: execnodes.h:2006
PlanState ps
Definition: execnodes.h:2004
void ExecParallelReinitialize(ParallelExecutorInfo *pei)
Definition: execParallel.c:345
void ExecShutdownGather ( GatherState node)

Definition at line 404 of file nodeGather.c.

References ExecParallelCleanup(), ExecShutdownGatherWorkers(), NULL, and GatherState::pei.

Referenced by ExecEndGather(), and ExecShutdownNode().

405 {
407 
408  /* Now destroy the parallel context. */
409  if (node->pei != NULL)
410  {
411  ExecParallelCleanup(node->pei);
412  node->pei = NULL;
413  }
414 }
static void ExecShutdownGatherWorkers(GatherState *node)
Definition: nodeGather.c:376
struct ParallelExecutorInfo * pei
Definition: execnodes.h:2006
void ExecParallelCleanup(ParallelExecutorInfo *pei)
Definition: execParallel.c:635
#define NULL
Definition: c.h:226