Re: [Testperf-general] Re: ExclusiveLock

Greg Stark <gsstark(at)mit(dot)edu> writes:
> Once upon a time when you formatted hard drives you actually gave them an
> interleave factor for a similar reason. These days you invariably use an
> interleave of 1, ie, store the blocks continuously. Whether that's because
> controllers have become fast enough to keep up with the burst rate or because
> the firmware is smart enough to handle the block interleaving invisibly isn't
> clear to me.

The impression I had was that disk drives no longer pay the slightest
attention to interleave specs, because the logical model implied by the
concept is too far removed from modern reality (on-disk buffering,
variable numbers of sectors per track, transparently remapped bad
sectors, yadda yadda).

And that's just at the hardware level ... who knows where the filesystem
is putting your data, or what the kernel I/O scheduler is doing with
your requests :-(

Basically I see the TODO item as a blue-sky research topic, not
something we have any idea how to implement. That doesn't mean it can't
be on the TODO list ...

regards, tom lane