Re: Memory leakage associated with plperl spi_prepare/spi_freeplan

Alex Hunsaker <badalex(at)gmail(dot)com> writes:
> On Tue, Feb 26, 2013 at 3:56 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)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