Hi, On 2022-02-10 17:13:52 +0900, Amit Langote wrote: > The attached patch implements this idea. Sorry for the delay in > getting this out and thanks to Robert for the off-list discussions on > this.
I did not follow this thread at all. And I only skimmed the patch. So I'm probably wrong. I'm a wary of this increasing executor overhead even in cases it won't help. Without this patch, for simple queries, I see small allocations noticeably in profiles. This adds a bunch more, even if !context->stmt->usesPreExecPruning: - makeNode(ExecPrepContext) - makeNode(ExecPrepOutput) - palloc0(sizeof(PlanPrepOutput *) * result->numPlanNodes) - stmt_execprep_list = lappend(stmt_execprep_list, execprep); - AllocSetContextCreate(CurrentMemoryContext, "CachedPlan execprep list", ... - ... That's a lot of extra for something that's already a bottleneck. Greetings, Andres Freund
