From: Theodore Ts'o <tytso@mit.edu>
To: Eric Sandeen <sandeen@redhat.com>
Cc: Ric Wheeler <ricwheeler@gmail.com>, Fredrick <fjohnber@zoho.com>,
Ric Wheeler <rwheeler@redhat.com>,
linux-ext4@vger.kernel.org, Andreas Dilger <adilger@dilger.ca>,
wenqing.lz@taobao.com
Subject: Re: ext4_fallocate
Date: Wed, 27 Jun 2012 15:30:34 -0400 [thread overview]
Message-ID: <20120627193034.GA3198@thunk.org> (raw)
In-Reply-To: <4FEA1F18.6010206@redhat.com>
On Tue, Jun 26, 2012 at 04:44:08PM -0400, Eric Sandeen wrote:
> >
> > I tried running this fio recipe on v3.3, which I think does a decent job of
> > emulating the situation (fallocate 1G, do random 1M writes into it, with
> > fsyncs after each):
> >
> > [test]
> > filename=testfile
> > rw=randwrite
> > size=1g
> > filesize=1g
> > bs=1024k
> > ioengine=sync
> > fallocate=1
> > fsync=1
A better workload would be to use a blocksize of 4k. By using a
blocksize of 1024k, it's not surprising that the metadata overhead is
in the noise.
Try something like this; this will cause the extent tree overhead to
be roughly equal to the data block I/O.
[global]
rw=randwrite
size=128m
filesize=1g
bs=4k
ioengine=sync
fallocate=1
fsync=1
[thread1]
filename=testfile
- Ted
next prev parent reply other threads:[~2012-06-27 19:30 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-25 6:42 ext4_fallocate Fredrick
2012-06-25 7:33 ` ext4_fallocate Andreas Dilger
2012-06-28 15:12 ` ext4_fallocate Phillip Susi
2012-06-28 15:23 ` ext4_fallocate Eric Sandeen
2012-06-25 8:51 ` ext4_fallocate Zheng Liu
2012-06-25 19:04 ` ext4_fallocate Fredrick
2012-06-25 19:17 ` ext4_fallocate Theodore Ts'o
2012-06-26 1:23 ` ext4_fallocate Fredrick
2012-06-26 13:13 ` ext4_fallocate Ric Wheeler
2012-06-26 17:30 ` ext4_fallocate Theodore Ts'o
2012-06-26 18:06 ` ext4_fallocate Fredrick
2012-06-26 18:21 ` ext4_fallocate Ric Wheeler
2012-06-26 18:57 ` ext4_fallocate Ted Ts'o
2012-06-26 19:22 ` ext4_fallocate Ric Wheeler
2012-06-26 18:05 ` ext4_fallocate Fredrick
2012-06-26 18:59 ` ext4_fallocate Ted Ts'o
2012-06-26 19:30 ` ext4_fallocate Ric Wheeler
2012-06-26 19:57 ` ext4_fallocate Eric Sandeen
2012-06-26 20:44 ` ext4_fallocate Eric Sandeen
2012-06-27 15:14 ` ext4_fallocate Eric Sandeen
2012-06-27 19:30 ` Theodore Ts'o [this message]
2012-06-27 23:02 ` ext4_fallocate Eric Sandeen
2012-06-28 11:27 ` ext4_fallocate Ric Wheeler
2012-06-29 19:02 ` ext4_fallocate Andreas Dilger
2012-07-02 3:03 ` ext4_fallocate Zheng Liu
2012-06-28 12:48 ` ext4_fallocate Theodore Ts'o
2012-07-02 3:16 ` ext4_fallocate Zheng Liu
2012-07-02 16:33 ` ext4_fallocate Eric Sandeen
2012-07-02 17:44 ` ext4_fallocate Jan Kara
2012-07-02 17:48 ` ext4_fallocate Ric Wheeler
2012-07-03 17:41 ` ext4_fallocate Zheng Liu
2012-07-03 17:57 ` ext4_fallocate Zach Brown
2012-07-04 2:23 ` ext4_fallocate Zheng Liu
2012-07-02 18:01 ` ext4_fallocate Theodore Ts'o
2012-07-03 9:30 ` ext4_fallocate Jan Kara
2012-07-04 1:15 ` ext4_fallocate Phillip Susi
2012-07-04 2:36 ` ext4_fallocate Zheng Liu
2012-07-04 3:06 ` ext4_fallocate Phillip Susi
2012-07-04 3:48 ` ext4_fallocate Zheng Liu
2012-07-04 12:20 ` ext4_fallocate Ric Wheeler
2012-07-04 13:25 ` ext4_fallocate Zheng Liu
2012-06-26 13:06 ` ext4_fallocate Eric Sandeen
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