From owner-freebsd-fs@FreeBSD.ORG  Thu Apr  9 13:29:36 2015
Return-Path: <owner-freebsd-fs@FreeBSD.ORG>
Delivered-To: freebsd-fs@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))
 (No client certificate requested)
 by hub.freebsd.org (Postfix) with ESMTPS id 141E1F6E
 for <freebsd-fs@freebsd.org>; Thu,  9 Apr 2015 13:29:36 +0000 (UTC)
Received: from blade.simplesystems.org (blade.simplesystems.org [65.66.246.74])
 (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id C403E925
 for <freebsd-fs@freebsd.org>; Thu,  9 Apr 2015 13:29:35 +0000 (UTC)
Received: from freddy.simplesystems.org (freddy.simplesystems.org
 [65.66.246.65])
 by blade.simplesystems.org (8.14.4+Sun/8.14.4) with ESMTP id t39DJok1024652;
 Thu, 9 Apr 2015 08:19:50 -0500 (CDT)
Date: Thu, 9 Apr 2015 08:19:50 -0500 (CDT)
From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
X-X-Sender: bfriesen@freddy.simplesystems.org
To: grarpamp <grarpamp@gmail.com>
Subject: Re: FreeBSD/ZFS on [HEAD] chews up memory
In-Reply-To: <CAD2Ti2_4S_yPgJdKxfb=_eQq5RezSTAa_M0V-EHf=y60k30RBQ@mail.gmail.com>
Message-ID: <alpine.GSO.2.01.1504090814560.4186@freddy.simplesystems.org>
References: <CAD2Ti2_4S_yPgJdKxfb=_eQq5RezSTAa_M0V-EHf=y60k30RBQ@mail.gmail.com>
User-Agent: Alpine 2.01 (GSO 1266 2009-07-14)
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
Cc: freebsd-fs@freebsd.org
X-BeenThere: freebsd-fs@freebsd.org
X-Mailman-Version: 2.1.18-1
Precedence: list
List-Id: Filesystems <freebsd-fs.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-fs>,
 <mailto:freebsd-fs-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-fs/>
List-Post: <mailto:freebsd-fs@freebsd.org>
List-Help: <mailto:freebsd-fs-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-fs>,
 <mailto:freebsd-fs-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 09 Apr 2015 13:29:36 -0000

On Thu, 9 Apr 2015, grarpamp wrote:

>> RAM amount might matter too. 12GB vs 32GB is a bit of a difference.
>
> Allow me to bitch hypothetically...
>
> We, and I, get that some FS need memory, just like kernel and
> userspace need memory to function. But to be honest, things
> should fail or slow gracefully. Why in the world, regardless of
> directory size, should I ever need to feed ZFS 10GB of RAM?

>From my reading of this list in the past month or so, I have seen 
other complaints about memory usage, but also regarding UFS and NFS 
and not just ZFS.  One is lead to think that the way the system uses 
memory for filesystems has changed.

As others have said, ZFS ARC should automatically diminish, but 
perhaps ZFS ARC is not responsible for the observed memory issues.

Bob
-- 
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/