From owner-freebsd-hackers  Fri Jun 29 22:57:55 2001
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Date: Sat, 30 Jun 2001 00:57:49 -0500
From: "Michael C . Wu" <keichii@iteration.net>
To: "E.B. Dreger" <eddy+public+spam@noc.everquick.net>
Cc: freebsd-smp@freebsd.org, freebsd-hackers@freebsd.org
Subject: Re: Quick question: AIO / SMP / process-based threading
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In-Reply-To: <Pine.LNX.4.20.0106300538250.19544-100000@www.everquick.net>; from eddy+public+spam@noc.everquick.net on Sat, Jun 30, 2001 at 05:47:49AM +0000
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On Sat, Jun 30, 2001 at 05:47:49AM +0000, E.B. Dreger scribbled:
| 1. Is AIO SMP-safe?

AIO is not safe, SMP or not.

| 2. If not, how could one force coherency?  (Read and rewrite locked
|    a word from each cache line?)  Is it worth the effort, or should
|    one not use AIO across process boundaries?

Don't use it.

| I'm asking primarily about 4.x, unless anyone has good guesses of
| how 5.x will be. ;-)
| 
| I'll also keep an eye out for KSEs... thanks to Terry and others
| for alerting me to those.  (KSEs really answer most of my recent
| questions, but I don't think that I can wait that long, nor do I
| have the kernel background to really offer any assistance in the
| KSE project...)
| 

KSE won't be available for a long time.  

-- 
+-----------------------------------------------------------+
| keichii@iteration.net         | keichii@freebsd.org       |
| http://iteration.net/~keichii | Yes, BSD is a conspiracy. |
+-----------------------------------------------------------+

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