Re: PGStream.ReceiveTupleV3 and Out of Memory

That did it! Thank you all!

-Dan

On Wed, Apr 27, 2011 at 2:23 PM, Dave Cramer <pg@fastcrypt.com> wrote:
> Probably because it is retrieving the entire result set at once.
>
> You may want to set fetch size to something other than 0 to get the
> driver to use a cursor (note you have to set autocommit to false)
>
> Dave Cramer
>
> dave.cramer(at)credativ(dot)ca
> http://www.credativ.ca
>
>
>
>
> On Wed, Apr 27, 2011 at 1:59 PM, digifork <digifork@gmail.com> wrote:
>> Hello All!
>>
>> I have a question that I hope someone can help me with. I have a very
>> large query against a PostgreSQL 8.2 database using an iBatis 2.3.4
>> RowHandler, postgresql-8.2 JDBC4 driver, and a 32-bit Java 1.6 JVM.
>> The reason why we use the RowHandler is because we know this is a big
>> query and want to handle it a row at a time.
>>
>> When I start the query, it takes some time to return the first row.
>> When the query is about to return the first row, there is a giant
>> spike in heap memory use and the the JVM runs out of memory. I was
>> able to snapshot the heap before it crashed. The culprit seems to be
>> this call:
>>
>> 97.4% - 632 MB - 17,776,474 alloc. org.postgresql.core.PGStream.ReceiveTupleV3
>>
>> I have analyzed the database and we have no rows that exceed 2K in
>> size; so I know the problem is not related to returning a giant single
>> row.
>>
>> Does anyone have any ideas why ReceiveTupleV3 is returning so much data?
>>
>> Thank you!
>>
>> -Dan
>>
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>