Re: some other backend died abnormally - Mailing list pgsql-bugs

From fredrik chabot
Subject Re: some other backend died abnormally
Date
Msg-id 3D90BF30.8020306@f6.nl
Whole thread Raw
In response to Bug #769: Slow vacuuming due to error in optimization  (pgsql-bugs@postgresql.org)
List pgsql-bugs
Tom Lane wrote:

>fredrik chabot <fredrik@f6.nl> writes:
>
>>so I migrated the database to a non-smp machine running RH 7.2 and the postgres
>>7.2.1-5 rpm's
>>
>>Kernel 2.4.7-10
>>
>>and I still get
>>
>>FATAL 1:  LWLockAcquire: can't wait without a PROC structure
>>
>>The code tells me this should never heppen :->
>>
>I don't think it should happen either ;-)  When do you see it exactly
>--- is it during startup of a fresh connection, or while executing
>queries in an existing backend, or ...?
>
Ok, short answer I don't know; long answer:

Most connections are "long-lived" connections staying up for hours on
end. There are somewhere form 6  upto ~75 connections open at a time
about 6 at night > 50 during "office hours". Both failures today where
in office hours and It happend about every hour in office hours on the
smp system and only once in the off hours.

I got it BTW twice while loading the data in the database. Simple stuff
begin; -thousands of inserts; commit; and then the next table.
I did not once fail during the test fase of the system. (one or two
users at a time)

So my hunch is that it happens when there has been a lot of operations
in one connection and a lot of other connections at the same time.

>
>
>            regards, tom lane
>
>PS: please don't send HTML mail to the lists, it's a pain to quote ...
>
>---------------------------(end of broadcast)---------------------------
>TIP 2: you can get off all lists at once with the unregister command
>    (send "unregister YourEmailAddressHere" to majordomo@postgresql.org)
>

pgsql-bugs by date:

Previous
From: Tom Lane
Date:
Subject: Re: some other backend died abnormally
Next
From: pgsql-bugs@postgresql.org
Date:
Subject: Bug #780: Timestamp shifted by one minute