followup: Rinky dink hamfest

From: Allison J Parent <allisonp_at_world.std.com>
Date: Mon Mar 29 18:22:29 1999

<I would mention that I had 128K in each of my Systems Group systems and
<never used it under CP/M. MP/M had a mechanism for cashing in on extra
<memory, but it was awkward at best under CP/M 2.2.
<
<Needless to say, the use of a RAMdisk would speed things up, but unless
<there was an extensive amount of software for managing it, and that took u
<too much TPA, even a RAMdisk didn't help much.

Way off. Caching disks for CP/M-any (especally 2.2) is a huge performance
boost. CPM suffers from waiting on the disk and often the difference
between a slow system and a fast one is how the disks were handled. Having
run ram disks, caches, caching controllers I have studied where the
bottlenecks are and the most common is the CPU spinning in PIO or worse
waiting for the sector to come around to do PIO.

the software over head for caching is small. once you go over 128 byte
sector size yo need a host buffer to deblock it... you can read a whole
track in and deblock that. Free cache.

Allison
Received on Mon Mar 29 1999 - 18:22:29 BST