Re: [HACKERS] A better way than tweaking NTUP_PER_BUCKET

[Stephen Frost]

* Stephen Frost (sfr...@snowman.net) wrote:
> * Simon Riggs (si...@2ndquadrant.com) wrote:
> > I don't see anything for 9.4 in here now.
> 
> Attached [...]

I'm apparently bad at this 'attaching' thing, particularly on this
subject.

Here it is.

        Thanks,

                Stephen

colordiff --git a/src/backend/executor/nodeHash.c b/src/backend/executor/nodeHash.c
new file mode 100644
index 6a2f236..a8a8168
*** a/src/backend/executor/nodeHash.c
--- b/src/backend/executor/nodeHash.c
*************** ExecChooseHashTableSize(double ntuples,
*** 489,496 ****
  		/* We expect the hashtable to fit in memory */
  		double		dbuckets;
  
! 		dbuckets = ceil(ntuples / NTUP_PER_BUCKET);
! 		dbuckets = Min(dbuckets, max_pointers);
  		nbuckets = (int) dbuckets;
  
  		nbatch = 1;
--- 489,495 ----
  		/* We expect the hashtable to fit in memory */
  		double		dbuckets;
  
! 		dbuckets = Min(ntuples, max_pointers);
  		nbuckets = (int) dbuckets;
  
  		nbatch = 1;

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