glenm@mako.UUCP (Glen McCluskey) (06/03/85)
Has anyone looked over the sources distributed by Ken Mitchum for the MSDOS version of JOVE? One of the problems with this version is that on a floppy system the swapping to a temporary file on disk will kill you. It appears after looking at ``temp.c'' that a provision has been made for doing in-memory buffering instead, but only for the VMUNIX version. Simply taking out the #ifdef should allow this to be done for MSDOS systems as well. Of course, you need lots of memory to do this. Has anyone tried this? Glen McCluskey ..tektronix!mako!glenm
km@cadre.ARPA (Ken Mitchum) (06/06/85)
>Has anyone looked over the sources distributed by >Ken Mitchum for the MSDOS version of JOVE? One of >the problems with this version is that on a floppy >system the swapping to a temporary file on disk will >kill you. > >It appears after looking at ``temp.c'' that a provision >has been made for doing in-memory buffering instead, >but only for the VMUNIX version. Simply taking out the >#ifdef should allow this to be done for MSDOS systems as >well. Of course, you need lots of memory to do this. >Has anyone tried this? > > Glen McCluskey > ..tektronix!mako!glenm Yes - swapping on a floppy-based system is very slow. This is mentioned in the documentation - however, I plead completely guilty to not looking at the problem before. I worked on JOVE on hard disk systems only, and only tried it on a floppy system briefly before distributing it. I also assumed most people would use Jove on a hard disk system, since just compiliing and linking all the files on a floppy system would take forever! I have never looked closely at the code in "temp.c" as it required no modification to work with MSDOS (sqeaky wheel gets the grease). I will try to take a look at the code and see how in-memory buffering works out. To use more memory with C86, it is necessary to redefine _MAXFMEM and _MINFMEM, which were not adjusted in the JOVE sources, so that a version would work with a minimum of memory (256K). My schedule is very busy at the moment, but I will post something to the net regarding this in the future, along with any code changes. Alternatively, any one else implementing in-memory buffering should post comments on their experiences. There are MANY problems with JOVE/MSDOS. It should be taken as a kludge which works, which is the spirit in which I worked on it. There are many optimizations and changes to be done, particularly with how the screen images are handled. Alas, I wish I had more time to spend on it. Ken Mitchum University of Pittsburgh