On Tue, 11 Feb 1997, Jonathan Stone wrote:

> The programmed-IO 3Com cards effectively require an interrupt and an
> explicit copy for every packet. This is supposedly a win for a
> dedicated server with a `squashed' IPX network stack.  The numbers I
> have suggest it's at best marginal, and perhaps worse than DMA, for
> 100Mbit speeds and a BSD networking stack.

The win, I think, is supposed to be that you can interrupt before
the packet has finished arriving, do the copy as it arrives, and
reduce latency.  How to take advantage of this under NetBSD is a
mystery to me, at least until Charles implements his `run device
drivers as threads' code.

cjs

Curt Sampson    cjs@portal.ca	   Info at http://www.portal.ca/
Internet Portal Services, Inc.	   Through infinite myst, software reverberates
Vancouver, BC  (604) 257-9400	   In code possess'd of invisible folly.