Very slow UPDATEs...

Good time of the day!

I've run into a strange problem and have no idea what/where to look...
Will be happy to get any input...

Situation is: simple updates takes, say, 5 minutes to complete...
E.g. (from psql)
test=> UPDATE progs SET acc = 1 WHERE id = 4601;
UPDATE 1
Time: 346451,14 ms

"id" is indexed and EXPLAIN shows that index is used. "acc" is not
indexed, so there shouldn't be any slowdown. Table is relatively small
- like 15000 records. Table is vacuumed and analyzed.

Need ideas on what to check / what to read / where to look, etc.

Thanks in advance!

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 Dmitri Touretsky ( dmitri@listsoft.ru )

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