Re: [WIP] speeding up GIN build with parallel workers

On Thu, Mar 17, 2016 at 11:42 PM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> I think here the comparison should be between the case of (active backend +
> 1 worker) with (passive backend + 1 worker) or (active backend + 2 worker)
> with (passive backend + 2 workers). I don't think it is good assumption
> that workers are always freely available and you can use them as and when
> required for any operation.

Strong +1. The pool of background workers is necessarily quite
limited and you can't just gobble them up. I'm not saying that it's
absolutely essential that the leader can also participate, but saying
that 1 active leader + 1 worker is only 2% faster than 1 passive
leader + 2 workers is not comparing apples to apples.

--
Robert Haas
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