From owner-freebsd-arm@freebsd.org Tue Mar 22 06:27:15 2016 Return-Path: Delivered-To: freebsd-arm@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 072A9AD801F for ; Tue, 22 Mar 2016 06:27:15 +0000 (UTC) (envelope-from peter@rulingia.com) Received: from vps.rulingia.com (vps.rulingia.com [103.243.244.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mail.rulingia.com", Issuer "Let's Encrypt Authority X1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 8FE7AAEA; Tue, 22 Mar 2016 06:27:14 +0000 (UTC) (envelope-from peter@rulingia.com) Received: from server.rulingia.com (c122-106-195-17.belrs5.nsw.optusnet.com.au [122.106.195.17]) by vps.rulingia.com (8.15.2/8.15.2) with ESMTPS id u2M6QgO2044432 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 22 Mar 2016 17:26:48 +1100 (AEDT) (envelope-from peter@rulingia.com) X-Bogosity: Ham, spamicity=0.000000 Received: from server.rulingia.com (localhost.rulingia.com [127.0.0.1]) by server.rulingia.com (8.15.2/8.15.2) with ESMTPS id u2M6Qa4w085351 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Tue, 22 Mar 2016 17:26:36 +1100 (AEDT) (envelope-from peter@server.rulingia.com) Received: (from peter@localhost) by server.rulingia.com (8.15.2/8.15.2/Submit) id u2M6QZLh085350; Tue, 22 Mar 2016 17:26:35 +1100 (AEDT) (envelope-from peter) Date: Tue, 22 Mar 2016 17:26:35 +1100 From: Peter Jeremy To: Warner Losh Cc: bob prohaska , freebsd-arm@freebsd.org, Ian Lepore Subject: Re: Effect of partitioning on wear-leveling Message-ID: <20160322062635.GD64087@server.rulingia.com> References: <20160321175952.GA83908@www.zefox.net> <1458586884.68920.96.camel@freebsd.org> <20160321221153.GB83908@www.zefox.net> <1458600070.68920.107.camel@freebsd.org> <20160322032832.GC83908@www.zefox.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="H+4ONPRPur6+Ovig" Content-Disposition: inline In-Reply-To: X-PGP-Key: http://www.rulingia.com/keys/peter.pgp User-Agent: Mutt/1.5.24 (2015-08-30) X-Greylist: Sender succeeded STARTTLS authentication, not delayed by milter-greylist-4.4.3 (vps.rulingia.com [103.243.244.15]); Tue, 22 Mar 2016 17:26:48 +1100 (AEDT) X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Mar 2016 06:27:15 -0000 --H+4ONPRPur6+Ovig Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2016-Mar-21 21:47:39 -0600, Warner Losh wrote: >So let=E2=80=99s do the math. 512MB cards tended to have write speeds of m= aybe 6MB/s. >At 6MB/s, that=E2=80=99s about 518MB/day, or one drive write per day. Most= SD cards, I think you dropped some zeroes there. 6MB/s =3D=3D 518,400MB/day =3D=3D 5= 18GB/day. That's 1000 drive writes/day - which is non-trivial. --=20 Peter Jeremy --H+4ONPRPur6+Ovig Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQJ8BAEBCgBmBQJW8OWbXxSAAAAAAC4AKGlzc3Vlci1mcHJAbm90YXRpb25zLm9w ZW5wZ3AuZmlmdGhob3JzZW1hbi5uZXRFRUIyOTg2QzMwNjcxRTc0RTY1QzIyN0Ux NkE1OTdBMEU0QTIwQjM0AAoJEBall6Dkogs0oewP/jETUqplvA7JwDb9AlK4zc5c VMN3Gym70pWp/scbtk1X0yyWryxtvSCH+R5RyNoJGEPfPD8+VFlVbRcTHfCzRL1E UImmQVqDytn/f2DGMMVOkdHXgy+5ADTZFigw6H51kp+5xmRaWm7KfyycGcxat00H 9qTHGoTfI3hp12YzWm0ym+fJ1NCqJsnKPpDleCu4saqAOMFcqdi5PPt1p+YOm5GN 0PhuuhkFISgTMaAHyTlQxWP2mRrjgPJlmgnwCAeTRtUHog+tqmLUN8mMbfZ0PzL8 Vu6R21wJ1/moil18c83PW1NotQry6emLA7eAaj9c3rDpqwJwXhLgY6MEfvFAFzm/ Sn3ziFPNJ+HsJHvdBVehUcrtBFLy0CyUbr1/zEuD+Y4y9GgG7GsYGgGW1XMDQEz0 rley36mUV+WxFrojvEzpnxsv5TU3Q3uhaNk+22z7YHXObTYgQoYWHBU45Cyu/DiC qoSaSxopwPoBsuLS9igY5kKk8cWxa4Mb+m2RjeqwXtx4AZfEw1hzCohE7q5/IRnk +Srfon80YxZOvPj1iqyP9+V2muW47/X1eJRatBwis/m5puHU+c2qRO+IG59biXbK u5Pcgq/yDXImc5fl5jPg1HKGsmYZscNrD0tzl59Bs3YMVTayRRDPjGGi0Hb4uott ICWObwKPhdbH5G3FjvvN =0hNm -----END PGP SIGNATURE----- --H+4ONPRPur6+Ovig--