Very slow performance

Good time of the day!

Sorry in advance if the question is too stupid... After some updates
in apllications my DB starts to respond ve-e-e-ry slowly. Looking in
the debug log I found:

1. Every query (including SELECTs) are "wrapped" into transactions.
E.g.
2002-12-04 01:54:12 [353] DEBUG: StartTransactionCommand
2002-12-04 01:54:12 [353] DEBUG: query: SELECT * FROM ....
2002-12-04 01:54:12 [353] DEBUG: CommitTransactionCommand

Is in normal or not? In code I use transactions only in some places
where few INSERTS or UPDATES goes one-by-one...

2. In the log pretty often I see following sequences:
2002-12-04 01:53:52 [353] DEBUG: StartTransactionCommand
2002-12-04 01:53:52 [353] DEBUG: query: SELECT * FROM ....
2002-12-04 01:53:52 [353] DEBUG: CommitTransactionCommand
2002-12-04 01:53:52 [353] DEBUG: StartTransactionCommand
2002-12-04 01:53:52 [353] DEBUG: query: BEGIN;ROLLBACK;
2002-12-04 01:53:52 [353] DEBUG: ProcessUtility: BEGIN;ROLLBACK;
2002-12-04 01:53:52 [353] DEBUG: CommitTransactionCommand
2002-12-04 01:53:52 [353] DEBUG: StartTransactionCommand
2002-12-04 01:53:52 [353] DEBUG: ProcessUtility: BEGIN;ROLLBACK;
2002-12-04 01:53:52 [353] DEBUG: CommitTransactionCommand
2002-12-04 01:54:12 [353] DEBUG: StartTransactionCommand
2002-12-04 01:54:12 [353] DEBUG: query: SELECT * FROM ...
2002-12-04 01:54:12 [353] DEBUG: CommitTransactionCommand

Strings like "ProcessUtility: BEGIN;ROLLBACK;" makes me warry that
something is wrong in here... But I don't see what is causing
RALLBACK... I suspect that slow performance came from here, because
often ROLLBACK is followed by a noticable delay (20-30 seconds).

I was trying to search the Net for this, but found nothing. I'll be
glad to any idea on where and what to look/check/read.
Just in case: PostgreSQL 7.2, FreeBSD.

Best regards,
Dmitri ( mailto:dmitri(at)listsoft(dot)ru )

New SOFT daily (RUS): http://www.listsoft.ru/
(ENG): http://www.listsoft.com/
Articles, tips : http://www.diskovod.ru/
---
Computer - A device designed to speed and automate errors.