On Mon, 25 May 2020 at 20:22, Guy Sotomayor <g...@shiresoft.com> wrote: > > I hadn't thought about IBMCACHE.SYS in *years*. I wrote it in its > entirety (there's even a patent that covers some of its operation). I > was in an AdTech (Advanced Technology) group at the time and was > looking at how to make disk operations faster in DOS at the time when I > came up with the idea.
Oh my word! Well I thank you for it. It helped a very great deal and made dozens of users of rather expensive IBM PS/2s in the Isle of Man very happy for a while in the late 1980s and early 1990s. :-) > There was a *huge* battle within IBM on if it should be released and in > order to do so, it was fairly well hidden. I can believe that! I think I read of it in a magazine and thought "never! I'd know!" -- so I looked and there it was. > There was a switch on config.sys statement for IBMCACHE.SYS to turn off > the write-back cache (e.g. writes would always go straight to disk). > As I recall, there was a 30 second timer for the writeback cache so > that if a disk block was "dirty" for more than 30 seconds it would get > flushed to disk. Yes, both true. I think I may have used the write-through switch for some people, but ISTR it reduced performance a little bit. Just teaching people to be a bit more patient was sometimes hard -- after all, this was a tool that appealed to the impatient! I think for them it was easier to teach them to press C-A-D and then wait for the RAM check before turning off. Or hit C-A-D, let it boot all the way, then turn it off! Great bit of work, if I may say so! -- Liam Proven – Profile: https://about.me/liamproven Email: lpro...@cix.co.uk – gMail/gTalk/gHangouts: lpro...@gmail.com Twitter/Facebook/LinkedIn/Flickr: lproven – Skype: liamproven UK: +44 7939-087884 – ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053
