ESIX- Additional Serial Ports?

[Uwe Doering]

john at jwt.UUCP (John Temples) writes:

>In article <1990Aug11.115912.10530 at pegasus.com> richard at pegasus.com (Richard Foulk) writes:
>>> [...]              BTW if you have Rev D of ESIX it will
>>>make use of the 16550 FIFO chip if you have it.
>>How does it compare to the FAS driver?
>
>I can't say how it compares with the FAS driver, but I did a quick
>benchmark and found that the ESIX driver runs *much* faster with a
>16550.  I just installed a DigiBoard DigiCHANNEL PC/4 board on my
>ESIX system.  This is a dumb four-port card with socketed UARTs.
>It's directly supported by ESIX's asy driver.  I replaced one of the
>16450's with a 16550A.  I connected a Wyse 50 terminal to the 16450
>port, logged in at 38400 baud, and did 'cat /etc/termcap'.  u386mon
>running on the console, with the system otherwise idle, showed 40% to
>45% CPU utilization on my 33 MHz 386.  Doing the same test on the 16550
>port showed 6% to 10% CPU utilization.  I think I'll be buying some
>more 16550's...

I tried this with FAS 2.07 beta (soon to be released) and NS16550A chips
(actually on ISC 386/ix, but this doesn't matter in this case) and
got 4% to 5%. But note that I used a 25 MHz cache board. With 33 MHz
the result will be even lower.

Therefor, still no way to avoid FAS. ;-)

       Uwe
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