Subject: Serial port driver
To: None <current-users@NetBSD.ORG>
From: D'Arcy J.M. Cain <>
List: current-users
Date: 05/19/1997 12:59:55
What is the latest story on this?  I remember 2 years ago people were
issuing patches to get around silo overflows and yet I still see them.
Is there something fundamentally different between the way we do serial
I/O and the way FreeBSD and Linux do it?  Those systems don't have any
problem with high speed serial transfers as far as I know whatever
ethernet card they use or if they use IDE drives.  (I recall discussion
which suggested that these could have a bearing on the problem.)  Why
do we still have to apologize for our serial performance?

I am trying to look at the code but two things stop me.  First of all
I can't find a good, clear discussion of how the driver interacts with
the other parts of the system, particularly with the device/terminal
routines interaction.  I have "The Design and Implementation of the
4.4BSD Operating System" but, while it is an excellent book, it lacks
the detail I am looking for.

Second, I know that many others have attacked this problem and yet we
still have it.  I'm afraid that my clumsy attempts will be redundant
at best.  Can someone who knows the whole story let us in on the real
problem here?  What direction should I be looking in.  Is there a "magic
cookie" somewhere that someone just never got around to integrating?

Inquiring minds want to know.  :-)

D'Arcy J.M. Cain                           |  Democracy is three wolves
darcy@{|}                  |  and a sheep voting on         
+1 416 424 2871     (DoD#0082)    (eNTP)   |  what's for dinner.
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