| Scott Marlowe 2005-10-31, 8:24 pm |
| On Mon, 2005-10-31 at 10:58, Simon Riggs wrote:
> On Mon, 2005-10-31 at 15:44 +0100, Martijn van Oosterhout wrote:
>
> Please read the rest of that thread. Those results and their conclusions
> were refuted in some detail, which lead to a number of optimizations in
> 8.0 and 8.1, mostly written by Tom.
>
>
> Your point was about cache efficiency as an argument for not increasing
> shared_buffers. Politely, I don't accept that argument. Clearly, there
> are some other considerations (for which I agree completely) but those
> don't prevent you increasing shared_buffers, they just place limits on
> your overall memory budget which could effect shared_buffers of course.
As I understand it, when the last backend referencing a collection of
data stops referencing it, that the buffers holding that data are
released, and if, a second later, another backend wants the data, then
it has to go to the Kernel for it again.
Is this still the case in 8.1?
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