Possible to speed up I/O subsystem of 5150?

From: Scott Stevens <chenmel_at_earthlink.net>
Date: Fri Dec 10 00:33:26 2004

On Thu, 9 Dec 2004 00:41:21 -0500, you wrote:

>On Wed, 8 Dec 2004 20:55:55 -0800 (PST), Fred Cisin <cisin_at_xenosoft.com> wrote:
>> > On Sun, 5 Dec 2004, Jim Leonard wrote:
>> > > I have a few IBM model 5150s that I use to code entries for programming
>> > > competitions and I'd like to try to speed up the hard disk in any way possible.
>> > > (If you're curious what my last project was, check out
>> > > http://www.pouet.net/prod.php?which=13722 to download and try it out -- it
>> > > displays full-screen full-motion color video with sync'd sound -- yes, on a
>> > > 4.77MHz 8088, no fooling). I've been looking for any way to speed up the hard
>> > > disk subsystem (currently WD1002 with Seagate ST225) and I simply can't get
>> > > more than 130KB/s out of the darn thing... so:
>>
>> Yes, there ARE some XT controllers that claim to do 1:1.
>> I do NOT remember WHICH ones.
>> Yes, there ARE some 8 bit IDE controllers,
>> but not all IDE drives will work with them.
>There are 8 bit SCSI controllers too. Once I sold two to one guy for
>$10. Both used NCR 53c90, both had ROM and were bootable.
>
>>
>> On Wed, 8 Dec 2004, Vintage Computer Festival wrote:
>> > Hey Jim.
>> > Are you allowed to use more modern versions of DOS (i.e. post 3.3)? If
>> > so, why not use a version that has SmartDrive built in? Better yet, use
>> > Speedstor or some equally capable caching utility. Or will caching not
>> > work for your purposes?
>>
>> SMARTDRV was bundled with Windoze 3.10, and will work with
>> some of the <3.30 DOS versions.
>> But you need to use 3.31 or newer to have any partitions
>> larger than 32M.
>XT's do not have more than 640K memory, thus SMARTDRV is not very useful.
>

True, but sometimes 640K is more than enough. I used to run a WWIV
BBS (the version 3 that was distributed only as Turbo Pascal source
code). It would run quite well in about 128K on a PC-XT clone. It
had a rather horrendous design, though, with each message posted by a
user being a discrete file in one horrendous big directory on the
drive. It made a ton of noise and was quite slow at scrolling through
the messages. I loaded in a big fat cache (about 300K,) using a TSR
made by Central Point Software, that ran in low DOS memory. It made
the machine run quite well for a single-user BBS. After a fresh boot,
it would rattle and whoosh the 5 meg hard drive for a bit as callers
ran through the message base, but then eventually settle down and run
almost entirely out of RAM, except for disk writes.

640K WAS enough for that application (ducks).

>vax, 9000
>
>>
>> The DOS 6.2x version of SMARTDRV has some very important
>> changes that "solved the problems with DoubleSpace":
>> it defaults to doing read caching, but NOT write caching,
>> if write caching is turned on, it no longer rearranges the sequence of the
>> writes,
>> when a program ends, it will not present the DOS prompt until the write
>> caching buffer is flushed.
>>
>> --
>> Grumpy Ol' Fred cisin_at_xenosoft.com
>>
Received on Fri Dec 10 2004 - 00:33:26 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:36:38 BST