Re: OutOfMemory hibernate scroll with 2M records | Postgresql 8.4 DB

Hi Greg

Thanks for your response. Hibernate works well when I change the DB to
SQL server but somehow the moment I point to Postgresql it start
generating OutOfMemory. Is there some configuration at DB end to ensure
it starts using the cursors.

See link: http://forum.springsource.org/archive/index.php/t-23170.html

Regards
Ankit

Greg Stark wrote:
> On Mon, Dec 21, 2009 at 12:54 PM, Ankit Kumar <ankitk@xebia.com> wrote:
>
>> I am running a Criteria.scroll() on postgresql on a DB containing 2M
>> records. The memory keeps increasing and finally it generates an
>> OutOfMemoryException. Please can you advice how to fix this.
>>
>> Postgresql DB version: 8.4
>> Postgresql Driver Used: postgresql-8.4-701.jdbc4.jar
>>
>> Some forums do mention that "scroll" is slow on Postgresql.
>>
>> Is this a known issue or we need to do something specific to make scroll
>> work on Postgresql?
>>
>>
>> Exception StackTrace:
>> java.lang.OutOfMemoryError: Java heap space
>>
>>
>
> This looks like a Java error, not a Postgres one. It looks like
> Hibernate is asking for the entire result set back from Postgres
> instead of using a scrollable cursor and is trying to hold it all in
> RAM. You should ask the Hibernate people if they plan to either spill
> to disk or use database-side cursors which certainly do if necessary.
>
>