From mboxrd@z Thu Jan  1 00:00:00 1970
From: "J. R. Okajima" <hooanon05@yahoo.co.jp>
Subject: Re: [PATCH v2] d_ino considered harmful
Date: Fri, 18 Jun 2010 03:04:08 +0900
Message-ID: <30568.1276797848@jrobl>
References: <20100616185913.GA15566@shell> <20100616195359.GA24382@shell> <1276721084.13788.53.camel@lap75545.ornl.gov>
Cc: Valerie Aurora <vaurora@redhat.com>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Christoph Hellwig <hch@infradead.org>,
	Miklos Szeredi <miklos@szeredi.hu>,
	Jan Blunck <jblunck@suse.de>,
	Jamie Lokier <jamie@shareable.org>,
	David Woodhouse <dwmw2@infradead.org>,
	Arnd Bergmann <arnd@arndb.de>,
	Andreas Dilger <adilger@sun.com>, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org
To: David Dillow <dillowda@ornl.gov>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <1276721084.13788.53.camel@lap75545.ornl.gov>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: linux-fsdevel.vger.kernel.org


David Dillow:
> For example, our main Lustre scratch space has over 285 million files in
> it, and using find -inum takes over 72 hours to walk the tree using
	:::
> Using ne2scan -- which uses libext2fs and combines the inode scan and
> the name lookup -- takes over 48 hours to generate a list of candidate
> files for the purge example. With an optimized inode scan and the custom
	:::

While I've never heard of ne2scan, I am interested in this simplified
problem such as "find the pathname(s) from an inum in a huge fs."
Is ne2scan essentially equivalent to "debugfs ncheck inum"?

About Valeris's patch, as long as "ls -i" is useful/helpful,
> +	/* Use of d_ino without st_dev is always buggy. */
is not true.


J. R. Okajima