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.janes@xxxxxxxxx>
On Sun, Aug 25, 2013 at 11:08 PM, 高健 <luckyjackgao@xxxxxxxxx> wrote:What is using the memory, the postgres backend or the client program?
> 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.
Cheers,
Jeff
