Re: [GENERAL] backend dies suddenly after a lot of error messages

A bug report on this was filled out against the 6.3 release as well.
Don't know the status of it, however :(

Mirko Kaffka wrote:
>
> Hi,
>
> We have problems with backend processes that close the channel because of
> palloc() failures. When an INSERT statement fails, the backend reports an
> error (e.g. `Cannot insert a duplicate key into a unique index') and
> allocates a few bytes more memory. The next SQL statement that fails
> causes the backend to allocate more memory again, etc. until we have no
> more virtual memory left. Is this a bug?
> We are using postgres 6.4.2 on FreeBSD 2.2.8.
>
> It also works with psql:
>
> toy=> create table mytable (i integer unique);
> NOTICE:  CREATE TABLE/UNIQUE will create implicit index mytable_i_key for
> table mytable
> CREATE
> toy=> \q
>
> ~ $ # now do a lot of inserts that cause error messages:
> ~ $ while true; do echo "INSERT INTO mytable VALUES (1);"; done | psql toy
> INSERT INTO mytable VALUES (1);
> ERROR:  Cannot insert a duplicate key into a unique index
> ...quite a lot of these messages
> INSERT INTO mytable VALUES (1);
> ERROR:  Cannot insert a duplicate key into a unique index
> INSERT INTO mytable VALUES (1);
>
> pqReadData() -- backend closed the channel unexpectedly.
>         This probably means the backend terminated abnormally before or
> while processing the request.
> We have lost the connection to the backend, so further processing is
> impossible.  Terminating.
>
> Hmm, why does the backend allocate more and more memory with each failed
> INSERT ?
> Any clues?
>
> Thanks,
> Mirko

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