From owner-freebsd-fs@FreeBSD.ORG Tue Nov 20 16:18:23 2012 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 81363F82 for ; Tue, 20 Nov 2012 16:18:23 +0000 (UTC) (envelope-from lists@eitanadler.com) Received: from mail-lb0-f182.google.com (mail-lb0-f182.google.com [209.85.217.182]) by mx1.freebsd.org (Postfix) with ESMTP id DEBF98FC08 for ; Tue, 20 Nov 2012 16:18:22 +0000 (UTC) Received: by mail-lb0-f182.google.com with SMTP id go10so3242114lbb.13 for ; Tue, 20 Nov 2012 08:18:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=eitanadler.com; s=0xdeadbeef; h=mime-version:sender:in-reply-to:references:from:date :x-google-sender-auth:message-id:subject:to:cc:content-type; bh=FAhuX9T6y5+ul/1CSmGx6JGvy4FcpZRn6kTvffpiRTE=; b=Wi4SJKMst6I5/7IHVwV1RYfUU6c62bvCeZAjui0f0twaFi8gGSMheF8KeYK+ATyr3J fFxD4YljsT0ly9v6mpF9z+U2LkWj1jkSAaR7WhPC28A/VON5BwSvKa+qkc1mxyfqYmdN NUIHrGNtyAOQUb+J9bmHwkItpNSOpCwT/xbdE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:sender:in-reply-to:references:from:date :x-google-sender-auth:message-id:subject:to:cc:content-type :x-gm-message-state; bh=FAhuX9T6y5+ul/1CSmGx6JGvy4FcpZRn6kTvffpiRTE=; b=gS2UBcU86JjPagOwvRv0mxuqOHNbELD377StSunX+Q7KaPIx5VuVifpQrHXlAW/r5x CcG9nfQ+LfLVQdkVgjg//QyaLiwtfmIorSkVZzyXfkAaaU2Vlg8Fv+e6BOGmrJ+EuPEv Koa6eZpi2kA/wZ3iyjlY/U1kyj2HB53bwb6Cs2AyncQMMe9+x3uVHRdG/vcXIYquHsDt i1dkLmss2V2Gtli+hGmSU7ByuWkyiZj/O2vgv2bTaqJYsitx2vzC6Dv5YQXt4Dy/tOZb uTn2W1FiBpr8z4FjjN1vWjlgCmhIIg+KYyddvQh0gSkM10uK8OADGOP6FuE4X0t/E7X/ EqaQ== Received: by 10.152.102.234 with SMTP id fr10mr15254296lab.28.1353428301420; Tue, 20 Nov 2012 08:18:21 -0800 (PST) MIME-Version: 1.0 Sender: lists@eitanadler.com Received: by 10.112.25.166 with HTTP; Tue, 20 Nov 2012 08:17:50 -0800 (PST) In-Reply-To: <48C81451-B9E7-44B5-8B8A-ED4B1D464EC6@bway.net> References: <57ac1f$gf3rkl@ipmail05.adl6.internode.on.net> <50A31D48.3000700@shatow.net> <57ac1f$gg70bn@ipmail05.adl6.internode.on.net> <48C81451-B9E7-44B5-8B8A-ED4B1D464EC6@bway.net> From: Eitan Adler Date: Tue, 20 Nov 2012 11:17:50 -0500 X-Google-Sender-Auth: U42zigreYx0-q52hH4CjQ_inG0A Message-ID: Subject: Re: ZFS FAQ (Was: SSD recommendations for ZFS cache/log) To: Charles Sprickman Content-Type: text/plain; charset=UTF-8 X-Gm-Message-State: ALoCoQnEdp/4jWB2kro6oXW1zKcFQe/0Chz8k0OdfeTqQSvoHZ5Am0McJpNFqIxAs5f6BkeJr/cf Cc: FreeBSD FS , Stephen McKay X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 20 Nov 2012 16:18:23 -0000 On 19 November 2012 23:59, Charles Sprickman wrote: > Wonderful to see some work on this. > > One of the great remaining zfs mysteries remains all the tunables > that are under "vfs.zfs.*". Obviously there are plenty of read-only > items there, but conflicting information gathered from random forum > posts and commit messages exist about what exactly one can do > regarding tuning beyond arc sizing. > > If you have any opportunity to work with the people who have ported > and are now maintaining zfs, it would be really wonderful to get > some feedback from them on what knobs are safe to twiddle and why. > I suspect many of the tunable items don't really have meaningful > equivalents in Sun's implementation since the way zfs falls under > the vfs layer in FreeBSD is so different. I'm working in general on the FAQ, not just on the ZFS section. I don't have the time to go in depth on this. :( I'll make you a deal though: If you could work with ZFS folk and provide the content in Q&A form I'll review it, turn it into docbook, and commit it. The entire point my FAQ commits has been to get other people involved. I can't do it all. -- Eitan Adler Source, Ports, Doc committer Bugmeister, Ports Security teams