From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1RBChC-0006kl-Ju for garchives@archives.gentoo.org; Tue, 04 Oct 2011 21:38:38 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 5F85121C2E9; Tue, 4 Oct 2011 21:38:10 +0000 (UTC) Received: from mail-wy0-f181.google.com (mail-wy0-f181.google.com [74.125.82.181]) by pigeon.gentoo.org (Postfix) with ESMTP id 5E19A21C276 for ; Tue, 4 Oct 2011 21:35:21 +0000 (UTC) Received: by wyf19 with SMTP id 19so1275248wyf.40 for ; Tue, 04 Oct 2011 14:35:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=from:reply-to:to:subject:date:user-agent:references:in-reply-to :mime-version:content-type:content-transfer-encoding:message-id; bh=uW506ZWAs78TpGgjQmUD/kEDUbhC2abLiwSbOIXloLA=; b=PVqVcfRcKuKcYSZyV9sLblimIFI5QQTQKF+7B3arKGgMlYKUSdamB7sQ2zMDIYmFIf cJXl58WOws2RIJUnCYeZkamfB9VpY2k99TwDQI8Zcro4416Tjsy+u78V6U8scOKCIinX miH4Psh+xlmsz9HRYvPGdk66Sa8v+9549ZWug= Received: by 10.227.198.14 with SMTP id em14mr2047625wbb.78.1317764120521; Tue, 04 Oct 2011 14:35:20 -0700 (PDT) Received: from dell_xps.localnet (230.3.169.217.in-addr.arpa. [217.169.3.230]) by mx.google.com with ESMTPS id j18sm7045693wbo.6.2011.10.04.14.35.19 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 04 Oct 2011 14:35:20 -0700 (PDT) From: Mick To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] Strange partition on USB stick Date: Tue, 4 Oct 2011 22:35:22 +0100 User-Agent: KMail/1.13.7 (Linux/2.6.39-gentoo-r3; KDE/4.6.5; x86_64; ; ) References: <201110032316.11950.michaelkintzios@gmail.com> <201110041939.30850.michaelkintzios@gmail.com> In-Reply-To: Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart7368407.UPECBkovDa"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <201110042235.24506.michaelkintzios@gmail.com> X-Archives-Salt: X-Archives-Hash: d0d356c4f02d84668a2645cf444ecb14 --nextPart7368407.UPECBkovDa Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Tuesday 04 Oct 2011 20:36:06 Paul Hartman wrote: > On Tue, Oct 4, 2011 at 1:39 PM, Mick wrote: > > On Tuesday 04 Oct 2011 17:18:18 Paul Hartman wrote: > >> You can create a real partition table on that device and reformat, if > >> you want. (Note that some flash-based devices suffer degraded > >> performance if you repartition or reformat them because they come with > >> specially-aligned FAT tables from the factory) > >=20 > > Interesting! I didn't know that. > >=20 > > I have repartitioned USB sticks in the past, but did not notice any > > change in performance - to be honest I didn't measure it. I assume then > > that if I were to re-partition for any reason I would need to stick to > > exactly the same start & finish shown by parted. > >=20 > > Re-formatting it ought to be OK though, as long as the fat16 shown by > > parted is correct. >=20 > I think filesystems other than FAT are aligned well already, assuming > your partitions are aligned, but with FAT there are some hoops you > must jump through. >=20 > There is a tool called flashbench that can test your drive > (destructively!) and figure out the most optimal block sizes. Here's a > great article about it and optimizing USB flash drives in general: > https://lwn.net/Articles/428584/ >=20 > And here is a forum thread about figuring out the FAT alignment: > http://www.patriotmemory.com/forums/showthread.php?3696 >=20 > The SD council makes a tool for MS Windows that optimally formats and > securely erases SD cards. Might be interesting to compare the results > of its format to a standard fdisk and mkfs.vfat in linux. >=20 > One thing I'm going to do next time I get a new SD card or flash drive > is take a snapshot of the boot sector/partition tables/FAT tables so > if I ever want to reformat it to FAT, I can restore the -- presumably > optimal -- factory layout. Excellent find! I've got some studying to do.=20 Thanks for sharing. :-) =2D-=20 Regards, Mick --nextPart7368407.UPECBkovDa Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (GNU/Linux) iEYEABECAAYFAk6LfBwACgkQVTDTR3kpaLZsygCfRsYgqw6PrVWleRsvJz9ktpWV BLIAn15t3cHffwW6WY+1LIXxlsgVGjI2 =uZI5 -----END PGP SIGNATURE----- --nextPart7368407.UPECBkovDa--