> On Oct 24, 2025, at 8:00 AM, cz via cctalk <[email protected]> wrote:
>
> OS level caching of disk devices is a gennable option in M+ with split I/D.
>
> It's actually pretty impressive; the system can do read-aheads, and also
> writes can be deferred (which makes turning off the system hot very bad). I
> think it can also cache the directory entry table and even a small cache of
> 256kb or so makes a nice performance difference.
It's also a standard feature in RSTS/E, which can allocate up to 496 kW to the
storage cache (plus additional memory, if you want, for a ramdisk). I haven't
tried to see what the performance numbers look like with and without, that
would be an interesting experiment.
paul
