From owner-freebsd-stable@FreeBSD.ORG Thu Aug 29 10:18:13 2013 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 30402102 for ; Thu, 29 Aug 2013 10:18:13 +0000 (UTC) (envelope-from freebsd-stable@m.gmane.org) Received: from plane.gmane.org (plane.gmane.org [80.91.229.3]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id DFA262796 for ; Thu, 29 Aug 2013 10:18:12 +0000 (UTC) Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1VEzIi-0004db-Tb for freebsd-stable@freebsd.org; Thu, 29 Aug 2013 12:18:04 +0200 Received: from lara.cc.fer.hr ([161.53.72.113]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 29 Aug 2013 12:18:04 +0200 Received: from ivoras by lara.cc.fer.hr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 29 Aug 2013 12:18:04 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-stable@freebsd.org From: Ivan Voras Subject: Re: Suggest changing dirhash defaults for FreeBSD 9.2. Date: Thu, 29 Aug 2013 12:17:50 +0200 Lines: 45 Message-ID: References: <521C9E85.4060801@UToledo.edu> <521D7552.5080008@UToledo.edu> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="----enig2FEIUTEQRIICQAPAWFEHB" X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: lara.cc.fer.hr User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:17.0) Gecko/20130322 Thunderbird/17.0.4 In-Reply-To: X-Enigmail-Version: 1.5.1 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.14 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, 29 Aug 2013 10:18:13 -0000 This is an OpenPGP/MIME signed message (RFC 4880 and 3156) ------enig2FEIUTEQRIICQAPAWFEHB Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 29/08/2013 03:32, Dewayne Geraghty wrote: > From the analysis perforned in 2009, and referenced earlier by Robert, = this > https://wiki.freebsd.org/DirhashDynamicMemory and other material at thi= s site, > indicates that the reclaimage interval is workload dependent and that 5= to 8 seconds seems, on average, to be adequate. I'm having trouble understanding what the graphs are saying - you seem to have almost consistently worse results with increasing dirhash memory and/or reclaim age. > Is the discussion, rather than (synthetic) workload > performance, sufficient to warrant changing the default settings by a f= actor of 12?=20 Yes, and also for an additional reason on top of what I've already said in @fs and @hackers: it will be at least 10 years before someone remembers to bumb this tunable again, so I consider a little overkill to be ok. ------enig2FEIUTEQRIICQAPAWFEHB Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (FreeBSD) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iEYEARECAAYFAlIfH88ACgkQ/QjVBj3/HSzBjwCfcys0NTVXWJEcgy1Oxw0vR2iW 8zEAoI3mw2cZ5rHzMZ+rQ2RlNNR580CY =/TYO -----END PGP SIGNATURE----- ------enig2FEIUTEQRIICQAPAWFEHB--