From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from len.romanrm.net ([176.31.121.172]:41593 "EHLO len.romanrm.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750846Ab2HaFCh (ORCPT ); Fri, 31 Aug 2012 01:02:37 -0400 Date: Fri, 31 Aug 2012 11:02:34 +0600 From: Roman Mamedov To: Martin Steigerwald Cc: linux-btrfs@vger.kernel.org, Josef Bacik , Mitch Harder Subject: Re: Varying Leafsize and Nodesize in Btrfs Message-ID: <20120831110234.031e23ee@natsu> In-Reply-To: <201208302334.49399.Martin@lichtvoll.de> References: <20120830162512.GA2879@localhost.localdomain> <201208302334.49399.Martin@lichtvoll.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/R=i2kfVrveG5jRI/2UbdRHY"; protocol="application/pgp-signature" Sender: linux-btrfs-owner@vger.kernel.org List-ID: --Sig_/R=i2kfVrveG5jRI/2UbdRHY Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Thu, 30 Aug 2012 23:34:49 +0200 Martin Steigerwald wrote: > I wanted to ask about 32k either. >=20 > I used 32k on one 2,5 inch external esata disk. But I never measured=20 > anything so far. >=20 > I wonder what a good value for SSD might be. I tend to not use anymore=20 > than 16k, but thats just some gut feeling right now. Nothing based on a=20 > well-founded explaination. If you look closely at https://oss.oracle.com/~mason/blocksizes/ , you will notice that 16K delivers almost all of the 32K's performance gains in "Read= ", while not suffering from slowdowns that 32K shows in "Create" and "Delete". I have chosen 16K for my new /home partition (on an SSD+HDD mdadm RAID1). But what disappointed me at the time, is that one can't seem to have a "mix= ed" allocation FS with non-default leaf/node sizes. --=20 With respect, Roman ~~~~~~~~~~~~~~~~~~~~~~~~~~~ "Stallman had a printer, with code he could not see. So he began to tinker, and set the software free." --Sig_/R=i2kfVrveG5jRI/2UbdRHY Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iEYEARECAAYFAlBARWoACgkQTLKSvz+PZwiK+gCeI72syQypXyxvJhh15OXC/Thl LTwAni/iXZNcj96Z7gLfXWaTxVHUxDop =xhQu -----END PGP SIGNATURE----- --Sig_/R=i2kfVrveG5jRI/2UbdRHY--