Re: java.lang.OutOfMemoryError: GC overhead limit exceeded

On 7/23/20 8:33 AM, Christophe combet wrote:
> Dear Rob,
>
> Total RAM is 512GB.
>
> Runtime.getRuntime().freeMemory() says: 7,630,918,904 at the time of
> issuing the query.
>
> jConsole timed out and it is impossible to reconnect. I did a screen
> capture at the time of the freeze.
>
> Le jeudi 23 juillet 2020 à 15:33:34 UTC+2, Rob Sargent
> <robjsargent(at)gmail(dot)com> a écrit :
>
>
>
>
> On 7/23/20 6:30 AM, Christophe combet wrote:
> >
> > Thank you for pointing the link between auto commit an buffering.
> >
> > autocommit=false: same exception.
> >
> > We try fetchSize.
> >
> > Thanks.
> > Le jeudi 23 juillet 2020 à 13:47:14 UTC+2, Vladimir Sitnikov
> > <sitnikov(dot)vladimir(at)gmail(dot)com <mailto:sitnikov(dot)vladimir(at)gmail(dot)com>> a
> écrit :
> >
> >
> >  >can you try switching to autocommit=false?
> >
> > + you probably need to configure fetchSize as well.
> >
> > Vladimir
>
> >
> You set the 8G limit on the java process but did you tell up the
> available RAM?  This query would require that about 3G be available to
> hold all the data. Can you use jConsole to establish how much memory is
> available at the time of issuing the query?
>
>
>
Upthread the select statement returned only "column1"
* We are doing a "SELECT column1 FROM table1 ODER BY column1;" (column1
* is varchar(14) and the table contains 130,080,790 rows), when the *
* exception occurs.
Are you reading in the bytea column as well?

And does it finish if you add more memory to the jvm (just for testing
purposes).