Re: memory leak regression 9.1 versus 8.1

On 05/09/2012 05:06 PM, Joe Conway wrote:
> OK, new script. This more faithfully represents the real life scenario,
> and reproduces the issue on HEAD with out-of-the-box config settings,
> versus 8.1 which completes the query having never exceeded a very modest
> memory usage:
>
> ---------------
> On pg 8.1 with out of the box config:
> VIRT  RES  SHR
> 199m  11m 3032
> ---------------
> On pg head with out of the box config:
> VIRT  RES  SHR
> 1671m 1.5g  16m
> ---------------

The attached one-liner seems to plug up the majority (although not quite
all) of the leakage.

do_convert_tuple() is allocating a new tuple for every row in the loop
and exec_stmt_return_next() is leaking it.

The query now finishes successfully. On pg head with attached patch and
out of the box config:
VIRT  RES  SHR
196m  35m  31m

This look sane/correct?

Joe

--
Joe Conway
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