From owner-freebsd-hackers  Thu Sep 11 01:36:47 1997
Return-Path: <owner-freebsd-hackers>
Received: (from root@localhost)
          by hub.freebsd.org (8.8.7/8.8.7) id BAA07532
          for hackers-outgoing; Thu, 11 Sep 1997 01:36:47 -0700 (PDT)
Received: from minor.stranger.com (stranger.vip.best.com [204.156.129.250])
          by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id BAA07518
          for <freebsd-hackers@freebsd.org>; Thu, 11 Sep 1997 01:36:39 -0700 (PDT)
Received: from dog.farm.org (dog.farm.org [207.111.140.47]) by minor.stranger.com (8.8.5/8.6.12) with ESMTP id BAA10869; Thu, 11 Sep 1997 01:42:10 -0700 (PDT)
Received: (from dk@localhost) by dog.farm.org (8.7.5/dk#3) id BAA06048; Thu, 11 Sep 1997 01:33:35 -0700 (PDT)
Date: Thu, 11 Sep 1997 01:33:35 -0700 (PDT)
From: Dmitry Kohmanyuk <dk@dog.farm.org>
Message-Id: <199709110833.BAA06048@dog.farm.org>
To: spork@super-g.com (spork)
Cc: freebsd-hackers@freebsd.org
Subject: Re: mmap and INN
Newsgroups: cs-monolit.gated.lists.freebsd.hackers
Organization: FARM Computing Association
Reply-To: dk+@ua.net
X-Newsreader: TIN [version 1.2 PL2]
Sender: owner-freebsd-hackers@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

In article <Pine.BSF.3.96.970911013258.16743A-100000@super-g.inch.com> you wrote:
> I've attached two messages I dug up out of the mail archives that seem to
> contradict each other.  Gary says mmap + INN is a good thing, and Mike
> says it's a bad thing...

> Who should I listen to?  We're close to going live with a 2.2-stable news
> machine, and I'm a bit confused about what INN optimizations to go with.

I am running FreeBSD 2.2.1-RELEASE with INN 1.5.1 and mmap (default 
setup from ports, only paths changed), and I indeed get zero-filled
4K blocks in my active file.   So my advice is that mmap() is broken.

I also have this suggestion:

From: Ollivier Robert <roberto@keltia.freenix.fr>
Message-ID: <19970720135853.17655@keltia.freenix.fr>

<<<
> hmm... why is uses
> ##  Should we msync when using mmap? Pick DO or DONT. Useful
> ##  with some slightly broken mmap implementations. (like HPUX and BSD/OS).
> #### =()<MMAP_SYNC            @<MMAP_SYNC>@>()=
> MMAP_SYNC             DONT
> ??
>
> should we declare FreeBSD mmap slightly broken?? ;-)

Yes. You must use this in addition of the MSYNC_3_ARG parameter. That
doesn't prevent the problem from happening though.
>>>

I haven't tried it yet;  the problem with active file doesn't manifest
itself often enough.  I plan to upgrade to 1.6 and see if the problem
persists, and then try MMAP_SYNC DONT.