From: Andreas Dilger Subject: Re: mke2fs options for large media archive filesystem Date: Mon, 3 Feb 2014 14:09:13 -0700 Message-ID: <7A86A0B9-5C08-42C9-A136-010CAAE384A1@dilger.ca> References: <52EE703B.3010703@gmail.com> Mime-Version: 1.0 (Mac OS X Mail 7.1 \(1827\)) Content-Type: multipart/signed; boundary="Apple-Mail=_C5955F28-F649-49F0-AF66-38053FE21963"; protocol="application/pgp-signature"; micalg=pgp-sha1 Cc: "linux-ext4@vger.kernel.org" , Bastien Traverse To: Vitaliy Filippov Return-path: Received: from mail-pb0-f51.google.com ([209.85.160.51]:52890 "EHLO mail-pb0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750784AbaBCVJU (ORCPT ); Mon, 3 Feb 2014 16:09:20 -0500 Received: by mail-pb0-f51.google.com with SMTP id un15so7559655pbc.38 for ; Mon, 03 Feb 2014 13:09:19 -0800 (PST) In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: --Apple-Mail=_C5955F28-F649-49F0-AF66-38053FE21963 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii On Feb 3, 2014, at 12:15 AM, Vitaliy Filippov = wrote: >> I would say that bigalloc is probably not what you want for an = archival system. It is relatively new and the space savings is minimal. = It is mostly for filesystems that need to allocate and free large files = rapidly. >=20 > And does it introduce any memory usage benefit? Maybe not on a 1TB, = but on a 32TB partition? :) > I.e. does the kernel keep full block bitmap (or maybe a tree of = blocks?) in memory, or does it read parts of it when they're needed? The kernel dynamically loads bitmaps when needed. Cheers, Andreas --Apple-Mail=_C5955F28-F649-49F0-AF66-38053FE21963 Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP using GPGMail -----BEGIN PGP SIGNATURE----- Comment: GPGTools - http://gpgtools.org iQIVAwUBUvAFenKl2rkXzB/gAQJXRBAAraJMrR3X0uf4BHDOiZWawiKqGOkV5thD dXLPiQvrQDtv3V1yIxSprZVzNaAzH3gAmvW8o7+WvvyMtIYkehRBex891fcLJk2k Fl23x3fKw4kQYacq8vC8D5WIUnINkKjR/0na9fISZxvihkxPGJN4pAcIBTrRW339 aoU2NQGUt+064zYDY+eaaL5HCE6v5/+nDh9BpiubhjtR6OII9lZ3iD98wvcQjGZp 4d5oY8ZLirL683dAJmWZFpz3hYmxR6NHvMNCUcjCj7CL0xktVhj1D+1pGCzo+vZt MlkWcd/bsSuKvW1VqgwAqQ6hVVojASKorxXNBBblFrX3HqQFiSqup4MoaHPX8ZT6 lt8RddXtcMxRDj22tPv+er609sy8TwiqMVmtMi+v73uqttzLmQzW4lrpihZfNboB RBfVTO5V2uhFjTWo4/Go7lCS1/cZx2nM+mvwb+eePBo0F4835OS0scJtZuMCO8oc 8gAXlrHtMXKpmUh8g47+rgAKLC36kgDvWwCwBwQjsrTDWUZ6xrg94kwMGB2zcxsR 2zzGWgAS1j7IwXrFpzYqvy4R2UKdiuyc/0fatosOntCJRwsttEzG7gvMtyAwocrA TsO+UMHZLYWzbA0OkgcP74Qxo1xLBx8LZ/0CeeOcscR+a5nLYGsx16eDlrCZPRBu /CqmSnUiq7U= =Npim -----END PGP SIGNATURE----- --Apple-Mail=_C5955F28-F649-49F0-AF66-38053FE21963--