From owner-freebsd-doc Thu May 24 2:10: 8 2001 Delivered-To: freebsd-doc@freebsd.org Received: from freefall.freebsd.org (freefall.freebsd.org [216.136.204.21]) by hub.freebsd.org (Postfix) with ESMTP id 054A037B43E for ; Thu, 24 May 2001 02:10:02 -0700 (PDT) (envelope-from gnats@FreeBSD.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.11.1/8.11.1) id f4O9A1B51335; Thu, 24 May 2001 02:10:01 -0700 (PDT) (envelope-from gnats) Date: Thu, 24 May 2001 02:10:01 -0700 (PDT) Message-Id: <200105240910.f4O9A1B51335@freefall.freebsd.org> To: freebsd-doc@freebsd.org Cc: From: Stefan `Sec` Zehl Subject: Re: docs/27599: md(4) manpage enhancement Reply-To: Stefan `Sec` Zehl Sender: owner-freebsd-doc@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org The following reply was made to PR docs/27599; it has been noted by GNATS. From: Stefan `Sec` Zehl To: Dima Dorfman Cc: FreeBSD-gnats-submit@freebsd.org Subject: Re: docs/27599: md(4) manpage enhancement Date: Thu, 24 May 2001 11:00:50 +0200 On Wed, May 23, 2001 at 08:57:23PM -0700, Dima Dorfman wrote: > sec@ice.42.org writes: > > --- /usr/export/src/share/man/man4/md.4 Sun Dec 31 03:11:56 2000 > > +++ ./md.4 Thu May 24 00:56:57 2001 > > @@ -59,6 +59,11 @@ > > with the kernel option > > .Dv MD_NSECT . > > .Pp > > +Be warned that due to kernel constraints such a > > +.Nm > > +disk cannot be bigger than a certain maximum size. > > +This size can be found in the 'Limit' column of 'vmstat -m'. > > +.Pp > > It looks to me like the man page already states this: > > The default maximum size of a md disk backed by malloc(9) is 20,000 sec- > tors of 512 bytes each. This can be changed with the kernel option > MD_NSECT. > > Perhaps it might make sense to mention vmstat(8), but I don't think > it's appropriate to add another paragraph, most of which just repeats > what has already been said. I'm sorry, but you misunderstand. The problem I mention has nothing to do with MD_NSECT. You can raise MD_NSECT all the way, but the mentioned 'Limit' column of 'vmstat -m' Is unaffected by that. That is exactly where this comes from. The default MD_NSECT is small enough to avoid any problems, but when you increase it, you run into that other, not yet documented limit which will HANG your machine. If my english isn't clear enough, feel free to improve it. But please add a warning to the manpage. CU, Sec -- There are too many priorities. One has to prioritize priorities. -- Wietse To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-doc" in the body of the message