database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-16 06:01:02 +03:00
Code Activity

Update Append's idea of first_partial_plan

Browse Source 
It turns out that after runtime partition pruning, Append's
first_partial_plan does not accurately represent partial plans to run,
if any of those got pruned.  This could limit participation of workers
in some partial subplans, if other subplans got pruned.  Fix it by
keeping an index of the first valid partial subplan in the state node,
determined at execnode Init time.

Author: David Rowley, with cosmetic changes by me.
Discussion: https://postgr.es/m/CAKJS1f8o2Yd=rOP=Et3A0FWgF+gSAOkFSU6eNhnGzTPV7nN8sQ@mail.gmail.com
This commit is contained in:
Alvaro Herrera
2018-04-17 16:19:48 -03:00
parent 55101549d5
commit b7e2cbc5b4
2 changed files with 19 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

24
src/backend/executor/nodeAppend.c
View File

@ -104,6 +104,7 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
PlanState **appendplanstates;
Bitmapset *validsubplans;
int nplans;
int firstvalid;
int i,
j;
ListCell *lc;
@ -207,19 +208,30 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
/*
* call ExecInitNode on each of the valid plans to be executed and save
* the results into the appendplanstates array.
*
* While at it, find out the first valid partial plan.
*/
j = i = 0;
firstvalid = nplans;
foreach(lc, node->appendplans)
{
if (bms_is_member(i, validsubplans))
{
Plan *initNode = (Plan *) lfirst(lc);
/*
* Record the lowest appendplans index which is a valid partial
* plan.
*/
if (i >= node->first_partial_plan && j < firstvalid)
firstvalid = j;
appendplanstates[j++] = ExecInitNode(initNode, estate, eflags);
}
i++;
}
appendstate->as_first_partial_plan = firstvalid;
appendstate->appendplans = appendplanstates;
appendstate->as_nplans = nplans;
@ -499,7 +511,6 @@ static bool
choose_next_subplan_for_leader(AppendState *node)
{
ParallelAppendState *pstate = node->as_pstate;
Append *append = (Append *) node->ps.plan;
/* Backward scan is not supported by parallel-aware plans */
Assert(ScanDirectionIsForward(node->ps.state->es_direction));
@ -556,7 +567,7 @@ choose_next_subplan_for_leader(AppendState *node)
}
/* If non-partial, immediately mark as finished. */
if (node->as_whichplan < append->first_partial_plan)
if (node->as_whichplan < node->as_first_partial_plan)
node->as_pstate->pa_finished[node->as_whichplan] = true;
LWLockRelease(&pstate->pa_lock);
@ -581,7 +592,6 @@ static bool
choose_next_subplan_for_worker(AppendState *node)
{
ParallelAppendState *pstate = node->as_pstate;
Append *append = (Append *) node->ps.plan;
/* Backward scan is not supported by parallel-aware plans */
Assert(ScanDirectionIsForward(node->ps.state->es_direction));
@ -629,14 +639,14 @@ choose_next_subplan_for_worker(AppendState *node)
/* Advance to the next valid plan. */
pstate->pa_next_plan = nextplan;
}
else if (node->as_whichplan > append->first_partial_plan)
else if (node->as_whichplan > node->as_first_partial_plan)
{
/*
* Try looping back to the first valid partial plan, if there is
* one. If there isn't, arrange to bail out below.
*/
nextplan = bms_next_member(node->as_valid_subplans,
append->first_partial_plan - 1);
node->as_first_partial_plan - 1);
pstate->pa_next_plan =
nextplan < 0 ? node->as_whichplan : nextplan;
}
@ -670,7 +680,7 @@ choose_next_subplan_for_worker(AppendState *node)
if (pstate->pa_next_plan < 0)
{
int nextplan = bms_next_member(node->as_valid_subplans,
append->first_partial_plan - 1);
node->as_first_partial_plan - 1);
if (nextplan >= 0)
pstate->pa_next_plan = nextplan;
@ -686,7 +696,7 @@ choose_next_subplan_for_worker(AppendState *node)
}
/* If non-partial, immediately mark as finished. */
if (node->as_whichplan < append->first_partial_plan)
if (node->as_whichplan < node->as_first_partial_plan)
node->as_pstate->pa_finished[node->as_whichplan] = true;
LWLockRelease(&pstate->pa_lock);

2
src/include/nodes/execnodes.h
View File

@ -1087,6 +1087,8 @@ struct AppendState
PlanState **appendplans; /* array of PlanStates for my inputs */
int as_nplans;
int as_whichplan;
int as_first_partial_plan; /* Index of 'appendplans' containing
* the first partial plan */
ParallelAppendState *as_pstate; /* parallel coordination info */
Size pstate_len; /* size of parallel coordination info */
struct PartitionPruneState *as_prune_state;