Re: Is there any method to limit resource usage in PG?

Hi:

Now the situation goes there:
In the testing environment,
even when my customer changed shared_buffers from 1024MB to 712MB or 512MB，
The total memory consumption is still almost the same.

I think that PG is always using as much resource as it can,
For a query and insert action,
Firstly , the data is pull into private memory of the backend process
which is service client.
Then, the backend process push the data into shared memory, here into
shared_buffers.
If the shared_buffers is not big enough to hold all the result data, then
part of data will be in shared_buffer,
the other data will still remain in backend process's memory.

Is my understanding right?

Best Regard

2013/8/27 Jeff Janes <jeff(dot)janes(at)gmail(dot)com>

> On Sun, Aug 25, 2013 at 11:08 PM, 高健 <luckyjackgao(at)gmail(dot)com> wrote:
> > Hello:
> >
> > Sorry for disturbing.
> >
> > I am now encountering a serious problem： memory is not enough.
> >
> > My customer reported that when they run a program they found the totall
> > memory and disk i/o usage all reached to threshold value(80%).
> >
> > That program is written by Java.
> > It is to use JDBC to pull out data from DB, while the query joined some
> > table together, It will return about 3000,000 records.
> > Then the program will use JDBC again to write the records row by row ,
> to
> > inert into another table in the DB.
>
> What is using the memory, the postgres backend or the client program?
>
> Cheers,
>
> Jeff
>