From: Johannes Stezenbach <js@linuxtv.org>
Date: Mon, 08 Jan 2007 13:41:47 GMT
Subject: Re: How git affects kernel.org performance
Message-ID: <20070108134147.GB5291@linuxtv.org>
In-Reply-To: <20070108125819.GA32756@thunk.org>

On Mon, Jan 08, 2007 at 07:58:19AM -0500, Theodore Tso wrote:
> 
> The fastest and probably most important thing to add is some readahead
> smarts to directories --- both to the htree and non-htree cases.  If
> you're using some kind of b-tree structure, such as XFS does for
> directories, preallocation doesn't help you much.  Delayed allocation
> can save you if your delayed allocator knows how to structure disk
> blocks so that a btree-traversal is efficient, but I'm guessing the
> biggest reason why we are losing is because we don't have sufficient
> readahead.  This also has the advantage that it will help without
> needing to doing a backup/restore to improve layout.

Would e2fsck -D help? What kind of optimization
does it perform?


Thanks,
Johannes