Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!nrl-cmf!cmcl2!brl-adm!adm!preece%fang@gswd-vms.gould.com
From: preece%fang@gswd-vms.gould.com (Scott E. Preece)
Newsgroups: comp.unix.wizards
Subject: Re: Unix Interrupts
Message-ID: <12036@brl-adm.ARPA>
Date: 29 Feb 88 23:36:51 GMT
Sender: news@brl-adm.ARPA
Lines: 26


  From: " Dr. Robin Lake " <rbl@nitrex.uucp>
> In article <3213@cup.portal.com> Chuck-Staatse@cup.portal.com writes:
> Does anyone know if UNIX supports a "Connect to Interrupt" facillity
> similar to VMS or RSX. Failing an "Out of the Box" solution, has
> anyone cobbled something together? Target system is a 68000 VME based
> system.
> Any takers?
----------
The forthcoming release 2.1 of UTX/32 (Gould's version of Unix) allows
you to connect either directly or indirectly to machine interrupts -- a
directly connected interrupt attaches user process code directly to the
low-level interrupt handler, and indirectly connected interrupt simply
causes a specified signal to be sent to the connected processes when the
interrupt occurs.

Typical times to enter the user's interrupt routine (assuming the
interrupt is not blocked) directly is 50-75us on a PN-6000; for an
indirectly connected interrupt a context switch has to happen, so the
time is order of 500us.  [These are ballpark numbers, a proper
performance report giving expected ranges is forthcoming.]

-- 
scott preece
gould/csd - urbana
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