SortMem...

mchron@aueb.gr wrote:

Hi
in the function ExecChooseHashTableSize()
(~/src/backend/executor/nodeHash.c)
are determined the bytes of the hash table. The correspondent code is:

/*
* Target in-memory hashtablesize in SortMem kilobytes
*/
hash_table_bytes = SortMem *1024L

(~/src/include/miscadmin.h)
extern DLLIMPORT int SortMem;

What SortMem represents? Where is evaluated and what is its value?

I want to create 2 hash tables. One for the inner and one for the outer rel.
What should be the hash_table_bytes in that case?

SortMem is a config value found in your postgresql.conf or using SHOW
SORTMEM.

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