From owner-freebsd-stable@FreeBSD.ORG Thu Sep 25 15:59:53 2008 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2A9271065695; Thu, 25 Sep 2008 15:59:53 +0000 (UTC) (envelope-from petefrench@ticketswitch.com) Received: from constantine.ticketswitch.com (constantine.ticketswitch.com [IPv6:2002:57e0:1d4e:1::3]) by mx1.freebsd.org (Postfix) with ESMTP id E4E088FC29; Thu, 25 Sep 2008 15:59:52 +0000 (UTC) (envelope-from petefrench@ticketswitch.com) Received: from dilbert.rattatosk ([10.64.50.6] helo=dilbert.ticketswitch.com) by constantine.ticketswitch.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.69 (FreeBSD)) (envelope-from ) id 1KitFw-000HI1-4h; Thu, 25 Sep 2008 16:59:52 +0100 Received: from petefrench by dilbert.ticketswitch.com with local (Exim 4.69 (FreeBSD)) (envelope-from ) id 1KitFw-0000XA-3B; Thu, 25 Sep 2008 16:59:52 +0100 To: koitsu@FreeBSD.org In-Reply-To: <20080925154357.GA16220@icarus.home.lan> Message-Id: From: Pete French Date: Thu, 25 Sep 2008 16:59:52 +0100 Cc: freebsd-stable@freebsd.org, admin@kkip.pl Subject: Re: vm.kmem_size settings doesn't affect loader? X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 25 Sep 2008 15:59:53 -0000 > The ARC uses kmem. "Should not use that much more memory" is a matter > of opinion; if an additional 64MB given to ARC causes kmem exhaustion Well, yes :-) Though I would think if I was runnign a system with 1.5 gig of kernel memory where an extra 64 meg was the differebce between life and death then I would be sailing too close to the wind for my liking anyway... > On the bright side, it's very easy to determine how much memory is being > dedicated to the ARC. sysctl kstat.zfs.misc will disclose this data > and I believe the following statistics are the ones you have to examine > for this issue: Now this is very useful stuff! I have compared mine to yours, and I am using more or less an extra 64 meg. which is kind what I expected. I also tried the script from the wiki page to estimate how much kernel memory I am using, and that hovers around the 300 meg mark. > Let's adhere to the K.I.S.S. concept, and not turn this thread into > a "tuning micro-management" thread. fair enough - I was just curious about the difference between 64 and 128 on the ARC cache, and now I have an answer, and more than enough info to do my own invetsigations as to what works for me. Thanks ;) -pete.