> The real question in my mind is why this turns into a bottleneck before
> the similar task of cleaning the 16MB XLOG segment does. I expected
> that one would need to be cracked before the CLOG switch time could
> possibly be an issue, but reports from the field seem to suggest
> otherwise.
Hm, on current CPUs zeroing 8kB of RAM should take less than 2 us... now
if it has to be written to disk, that's another story !
