Re: Excessive memory usage in multi-statement queries w/ partitioning

On Thu, 23 May 2019 at 17:55, Andreas Seltenreich
<andreas(dot)seltenreich(at)credativ(dot)de> wrote:
> a customer reported excessive memory usage and out-of-memory ERRORs
> after introducing native partitioning in one of their databases. We
> could narrow it down to the overhead introduced by the partitioning when
> issuing multiple statements in a single query.

"multiple statements in a single query", did you mean to write session
or maybe transaction there?

Which version?

I tried your test case with REL_11_STABLE and I see nowhere near as
much memory used in MessageContext.

After repeating the query twice, I see:

MessageContext: 8388608 total in 11 blocks; 3776960 free (1 chunks);
4611648 used
Grand total: 8388608 bytes in 11 blocks; 3776960 free (1 chunks); 4611648 used
MessageContext: 8388608 total in 11 blocks; 3776960 free (1 chunks);
4611648 used
Grand total: 8388608 bytes in 11 blocks; 3776960 free (1 chunks); 4611648 used

which is quite a long way off the 252MB you're getting.

perhaps I'm not testing with the same version as you are.

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David Rowley http://www.2ndQuadrant.com/
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