From owner-freebsd-arm@freebsd.org Thu Mar 23 15:07:42 2017 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 3EEC3D19022 for ; Thu, 23 Mar 2017 15:07:42 +0000 (UTC) (envelope-from ian@freebsd.org) Received: from outbound1b.ore.mailhop.org (outbound1b.ore.mailhop.org [54.200.247.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 219B41DBD for ; Thu, 23 Mar 2017 15:07:41 +0000 (UTC) (envelope-from ian@freebsd.org) X-MHO-User: 730135a2-0fda-11e7-bfb5-0d159cd3c324 X-Report-Abuse-To: https://support.duocircle.com/support/solutions/articles/5000540958-duocircle-standard-smtp-abuse-information X-Originating-IP: 73.78.92.27 X-Mail-Handler: DuoCircle Outbound SMTP Received: from ilsoft.org (unknown [73.78.92.27]) by outbound1.ore.mailhop.org (Halon) with ESMTPSA id 730135a2-0fda-11e7-bfb5-0d159cd3c324; Thu, 23 Mar 2017 15:07:36 +0000 (UTC) Received: from rev (rev [172.22.42.240]) by ilsoft.org (8.15.2/8.15.2) with ESMTP id v2NF7WVG003985; Thu, 23 Mar 2017 09:07:32 -0600 (MDT) (envelope-from ian@freebsd.org) Message-ID: <1490281652.58015.71.camel@freebsd.org> Subject: Re: Identifying counterfeit microSD cards on a Beaglebone Black From: Ian Lepore To: "Dr. Rolf Jansen" , freebsd-arm@freebsd.org Date: Thu, 23 Mar 2017 09:07:32 -0600 In-Reply-To: <70C95FC9-4B0A-4DA4-9857-EFAF41522D1B@obsigna.com> References: <1489864043.40576.219.camel@freebsd.org> <16B03E70-00E6-4C17-9A9A-8601F4C07364@obsigna.com> <2F7D5F42-E50A-4761-9EEC-DC873BD7D0AB@obsigna.com> <70C95FC9-4B0A-4DA4-9857-EFAF41522D1B@obsigna.com> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.18.5.1 FreeBSD GNOME Team Port Mime-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 23 Mar 2017 15:07:42 -0000 On Thu, 2017-03-23 at 00:42 -0300, Dr. Rolf Jansen wrote: > Am 21.03.2017 um 13:25 schrieb Luiz Otavio O Souza m>: > > > > On 19 March 2017 at 18:45, Dr. Rolf Jansen wrote: > > > > > > Am 18.03.2017 um 21:30 schrieb Dr. Rolf Jansen: > > > > > > > > Am 18.03.2017 um 16:07 schrieb Ian Lepore: > > > > > > > > > > On Sat, 2017-03-18 at 15:03 -0300, Dr. Rolf Jansen wrote: > > > > > > > > > > > > Am 18.03.2017 um 12:30 schrieb Warner Losh: > > > > > > > > > > > > > > > > > > > > > On Sat, Mar 18, 2017 at 8:44 AM, Dr. Rolf Jansen > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > I bought a 16 GB microSDHC SanDisk chip rated at 4 MB/s > > > > > > > > write > > > > > > > > speed for use with my Beaglebone Black. > > > > > > > > > > > > > > > > The internal flash offers practical write speeds in the > > > > > > > > range of > > > > > > > > 2 to 3 MB/s when copying data to it from a NFSv4 volume > > > > > > > > depending > > > > > > > > on the size of the files being copied. Executing the > > > > > > > > same copy > > > > > > > > operation with said microSDHC card as the target I see > > > > > > > > only 0.1 > > > > > > > > to 0.2 MB/s (less than 1/10). > > > > > > > > > > > > > > > > I suspect now that I got a counterfeited card. Before I > > > > > > > > dump it, > > > > > > > > I would like to run a definitive non-destructive test, > > > > > > > > preferably > > > > > > > > on the Beaglebone Black, and I would like to ask you > > > > > > > > for > > > > > > > > suggestions. > > [picking a random message to reply] > > > > I just saw an email from SanDisk support (whatever this means) > > where > > they claim the only supported model for this kind of use is the > > high-endurance series: > > https://www.sandisk.com/home/memory-cards/microsd-cards/high-endura > > nce-microsd > > > > This same email says that running any kind of OS in any of the > > other > > card models automatically breaks the warranty. > Luiz, thank you very much for the note. Do you know, whether this > high endurance XC card is compatible with the Beaglebone Black? > > Best regards > > Rolf I would assume that it is, they're typically just standard sd cards with flash arrays based on SLC technology and with a lot of extra space for reassigning bad blocks (a card that claims 8gb capacity could actually have 4x that many blocks or more available internally). But be aware that high-endurance or industrial-rated cards can be very expensive.  I think at work we pay around $40 each for industrial-rated 8gb cards.  (One of them was included in those test results I posted, and the performance was among the best, at least you get something for all that extra money.) -- Ian