Re: [HACKERS] Effect of changing the value for PARALLEL_TUPLE_QUEUE_SIZE

On Fri, Jun 2, 2017 at 9:01 AM, Amit Kapila <amit.kapila16@gmail.com> wrote:
> Your reasoning sounds sensible to me.  I think the other way to attack
> this problem is that we can maintain some local queue in each of the
> workers when the shared memory queue becomes full.  Basically, we can
> extend your "Faster processing at Gather node" patch [1] such that
> instead of fixed sized local queue, we can extend it when the shm
> queue become full.  I think that way we can handle both the problems
> (worker won't stall if shm queues are full and workers can do batched
> writes in shm queue to avoid the shm queue communication overhead) in
> a similar way.

We still have to bound the amount of memory that we use for queueing
data in some way.

-- 
Robert Haas
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