Re: [HACKERS] some problems with new locking code

Bruce Momjian <maillist@candle.pha.pa.us>

From: Bruce Momjian <maillist@candle.pha.pa.us>
To: vadim@sable.krasnoyarsk.su (Vadim B. Mikheev)
Cc: hackers@postgreSQL.org
Date: 1998-02-24T19:56:58Z
Lists: pgsql-hackers
> 
> I created simple table (just single int4 attr) with index on it
> and tried to reproduce reported problems with BTP_CHAIN flag
> (without success, unfortunately ?) by inserting data by 3-4 psql-s 
> simultaneously. No problems with 2 clients. But when 3rd psql
> starts one of psql-s becomes blocked for long time (a minutes). 
> After some time blocked process may continue insertion but 
> another process is sleeping instead of wake-uped proc. The same
> with 4 psql-s: one of process is always sleeping!

Thanks for finding this, Vadim.  I had meant to re-run my locking tests
on the new code before the 6.3 final, but had not done it yet.  I ran
them now, and they didn't work as they should.  It is fixed now.

The problem was that I was incrementing a counter in a while conditional
test, even though I was not executing the loop, and the counter was used
in the next loop.

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