On Fri, Nov 28, 2008 at 8:08 PM, Grzegorz Jaskiewicz <[EMAIL PROTECTED]> wrote: > work_mem = 128140 # min 64, size in KB > maintenance_work_mem = 65535 # min 1024, size in KB
Incidentally it's very odd to see maintenance_work_mem less than work_mem. work_mem is used by regular queries and maintenance_work_mem by things like create index. > AggContext: 1981800448 total in 250 blocks; 3768 free (117 chunks); > 1981796680 used > TupleHashTable: 1158668312 total in 150 blocks; 465512 free (580 > chunks); 1158202800 used Er, yeah. This is a known problem and it would be really nice to fix it. However nobody's come up with any bright ideas for fixing it and disabling hash aggregates doesn't seem worth it. The problem only occurs when Postgres dramaticalyl misestimates the number of hash buckets needed for hash aggregates. Can you post the EXPLAIN for your query? you might have to analyze your tables again, and possibly raise the stats target for the columns you're aggregating. Failing that you could set enable_hashaggregate to false for this query. -- greg -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
