Re: Memory leakage associated with plperl spi_prepare/spi_freeplan - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Memory leakage associated with plperl spi_prepare/spi_freeplan
Date
Msg-id 1706.1362191927@sss.pgh.pa.us
Whole thread Raw
In response to Re: Memory leakage associated with plperl spi_prepare/spi_freeplan  (Alex Hunsaker <badalex@gmail.com>)
Responses Re: Memory leakage associated with plperl spi_prepare/spi_freeplan  (Alex Hunsaker <badalex@gmail.com>)
List pgsql-hackers
Alex Hunsaker <badalex@gmail.com> writes:
> On Tue, Feb 26, 2013 at 3:56 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> I'm inclined to think the right fix is to make a small memory context
>> for each prepared plan made by plperl_spi_prepare().  The qdesc for it
>> could be made right in the context (getting rid of the unchecked
>> malloc's near the top of the function), the FmgrInfos and their
>> subsidiary data could live there too, and plperl_spi_freeplan could
>> replace its retail free's with a single MemoryContextDelete.

> Seemed fairly trivial, find the above approach in the attached.

Applied with some fixes.

> I added a
> CHECK_FOR_INTERRUPTS() at the top of plperl_spi_prepare(), it was fairly
> annoying that I couldn't ctrl+c my way out of test function.

Good idea, but it wasn't safe where it was --- needs to be inside the
PG_TRY(), so as to convert from postgres to perl error handling.

> One annonce is it still leaks :-(.

I fixed that, at least for the function-lifespan leakage from
spi_prepare() --- is that what you meant?

> It would be nice to squish the other leaks due to perm_fmgr_info()... but
> this is a start.

Yeah, I'm sure there's more left to do in the area --- but at least you
can create and free plans without it leaking.
        regards, tom lane



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