On 2018-04-30 14:59:31 +1200, Thomas Munro wrote:
> Hi,
>
> In EXPLAIN (BUFFERS), there are two kinds of cache misses that show up
> as "reads" when in fact they are not reads at all:
>
> 1. Relation extension, which in fact writes a zero-filled block.
> 2. The RBM_ZERO_* modes, which provoke neither read nor write.
Just for understanding: 2) can never happen for buffers showing up in
EXPLAIN, right?
I'm not saying you shouldn't fix the accounting...
Greetings,
Andres Freund