From: Ted Ts'o <tytso@mit.edu>
To: Yongqiang Yang <xiaoqiangnk@gmail.com>
Cc: Phillip Susi <phillsusi@gmail.com>,
Andreas Dilger <adilger@whamcloud.com>,
Lukas Czerner <lczerner@redhat.com>,
Jacek Luczak <difrost.kernel@gmail.com>,
"linux-ext4@vger.kernel.org" <linux-ext4@vger.kernel.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
"linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
Subject: Re: getdents - ext4 vs btrfs performance
Date: Tue, 13 Mar 2012 22:51:08 -0400 [thread overview]
Message-ID: <20120314025108.GF15379@thunk.org> (raw)
In-Reply-To: <CAGBYx2ZQk+kobPj5ff0NKEfK_-kD0NK4WiNUruF=d443PV-NSw@mail.gmail.com>
On Wed, Mar 14, 2012 at 10:48:17AM +0800, Yongqiang Yang wrote:
> What if we use inode number as the hash value? Does it work?
The whole point of using the tree structure is to accelerate filename
-> inode number lookups. So the namei lookup doesn't have the inode
number; the whole point is to use the filename to lookup the inode
number. So we can't use the inode number as the hash value since
that's what we are trying to find out.
We could do this if we have two b-trees, one indexed by filename and
one indexed by inode number, which is what JFS (and I believe btrfs)
does.
- Ted
next prev parent reply other threads:[~2012-03-14 2:51 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-29 13:52 getdents - ext4 vs btrfs performance Jacek Luczak
2012-02-29 13:55 ` Jacek Luczak
2012-02-29 14:07 ` Jacek Luczak
2012-02-29 14:21 ` Jacek Luczak
2012-02-29 14:42 ` Chris Mason
2012-02-29 14:55 ` Jacek Luczak
2012-03-01 13:35 ` Jacek Luczak
2012-03-01 13:50 ` Hillf Danton
2012-03-01 14:03 ` Jacek Luczak
2012-03-01 14:18 ` Chris Mason
2012-03-01 14:43 ` Jacek Luczak
2012-03-01 14:51 ` Chris Mason
2012-03-01 14:57 ` Jacek Luczak
2012-03-01 18:42 ` Ted Ts'o
2012-03-02 9:51 ` Jacek Luczak
2012-03-01 4:44 ` Theodore Tso
2012-03-01 14:38 ` Chris Mason
2012-03-02 10:05 ` Jacek Luczak
2012-03-02 14:00 ` Chris Mason
2012-03-02 14:16 ` Jacek Luczak
2012-03-02 14:26 ` Chris Mason
2012-03-02 19:32 ` Ted Ts'o
2012-03-02 19:50 ` Chris Mason
2012-03-05 13:10 ` Jan Kara
2012-03-03 22:41 ` Jacek Luczak
2012-03-04 10:25 ` Jacek Luczak
2012-03-05 11:32 ` Jacek Luczak
2012-03-06 0:37 ` Chris Mason
2012-03-08 17:02 ` Phillip Susi
2012-03-09 11:29 ` Lukas Czerner
2012-03-09 14:34 ` Chris Mason
2012-03-10 0:09 ` Andreas Dilger
2012-03-10 4:48 ` Ted Ts'o
2012-03-11 10:30 ` Andreas Dilger
2012-03-11 16:13 ` Ted Ts'o
2012-03-15 10:42 ` Jacek Luczak
2012-03-18 20:56 ` Ted Ts'o
2012-03-13 19:05 ` Phillip Susi
2012-03-13 19:53 ` Ted Ts'o
2012-03-13 20:22 ` Phillip Susi
2012-03-13 21:33 ` Ted Ts'o
2012-03-14 2:48 ` Yongqiang Yang
2012-03-14 2:51 ` Ted Ts'o [this message]
2012-03-14 14:17 ` Zach Brown
2012-03-14 16:48 ` Ted Ts'o
2012-03-14 17:37 ` Zach Brown
2012-03-14 8:12 ` Lukas Czerner
2012-03-14 9:29 ` Yongqiang Yang
2012-03-14 9:38 ` Lukas Czerner
2012-03-14 12:50 ` Ted Ts'o
2012-03-14 14:34 ` Lukas Czerner
2012-03-14 17:02 ` Ted Ts'o
2012-03-14 19:17 ` Chris Mason
2012-03-14 14:28 ` Phillip Susi
2012-03-14 16:54 ` Ted Ts'o
2012-03-10 3:52 ` Ted Ts'o
2012-03-15 7:59 ` Jacek Luczak
-- strict thread matches above, loose matches on Subject: below --
2012-02-29 13:31 Jacek Luczak
2012-02-29 13:51 ` Chris Mason
2012-02-29 14:00 ` Lukas Czerner
2012-02-29 14:05 ` Chris Mason
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