Date : Wed, 11 Jan 1984 21:40:07 EST
From : Keith Petersen <w8sdz@brl-bmd>
Subject: Re: buffer size in mdm716
Please tell Irv Hoff that Bob Plouffe and Ron Fowler already have MDM717
"in progress" and we should have something forthcoming from them with
these fixes in about a week. I'd hate to see all that good stuff that
Bob Plouffe put in MDM716 "stripped out" by Irv "because he doesn't
agree with it" or "doesn't like it". That's how we lost the "retry
after ten errors" option, amoung other things.
On the subject of the 2k buffer size. This is true ONLY for the
protocol file transfer mode. It does not affect the terminal
capture mode. It was done after NUMEROUS complaints from people
with slower disk systems which took so long writing the 16k buffer
out (and consequently closing that extent and opening the next
in the directory) that they lost the next sector and several tries
from the sender. In many cases this caused the transfer to abort.
The 2k buffer was chosen MANY versions back (when the program was
MODEM2) as an acceptable compromise between disk access speed
and the improvement in receiving speed by putting the characters
into the buffer instead of writing every sector (which was the
way Ward Christensen's old original MODEM program worked) to the
disk.