Re: Limiting memory allocation

Bruce Momjian <bruce@momjian.us> writes:
> On Tue, May 24, 2022 at 07:40:45PM -0400, Tom Lane wrote:
>> (1) There are not a predetermined number of allocations.  For example,
>> if we do a given join as nestloop+inner index scan, that doesn't require
>> any large amount of memory; but if we do it as merge or hash join then
>> it will consume memory.

> Uh, we know from the plan whether we are doing a nestloop+inner or merge
> or hash join, right?  I was suggesting we look at the plan before
> execution and set the proper percentage of work_mem for each node.

Then you just rendered all the planner's estimates fantasies.

            regards, tom lane