From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ryusuke Konishi Subject: Re: Split some metadata onto separate device? Date: Wed, 08 Jun 2011 21:58:03 +0900 (JST) Message-ID: <20110608.215803.224753719.ryusuke@osrg.net> References: <20110604.022621.01482278.ryusuke@osrg.net> <201106031942.29133.dexen.devries@gmail.com> <20110608.214852.237935973.ryusuke@osrg.net> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20110608.214852.237935973.ryusuke-sG5X7nlA6pw@public.gmane.org> Sender: linux-nilfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: Text/Plain; charset="us-ascii" To: dexen.devries-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Cc: linux-nilfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org On Wed, 08 Jun 2011 21:48:52 +0900 (JST), Ryusuke Konishi wrote: > On Fri, 3 Jun 2011 19:42:28 +0200, dexen deVries wrote: > > By the way, it seems to me that the in-kernel GC does not attempt to > > de- fragment files. Is that the case? If so, would probably mean > > extents would not help very much for fragmented files. Also, on > > magnetic media, a lot of seeking happens in case of fragmented > > files. > > Yes, but extents will decrease the amount of metadata, and this has > potential for speed up. > > NILFS2 uses 32 bytes metadata per disk block at present. I guess you > know that the number of DAT blocks are actually indispensable through > analysis using the dumpseg tool. Oh, looks confusing. I meant the amount of DAT blocks is not negligible. Regards, Ryusuke Konishi -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html