From: Ted Ts'o <tytso@mit.edu>
To: "K. Richard Pixley" <rich@noir.com>
Cc: Mike Fedyk <mfedyk@mikefedyk.com>, Josef Bacik <josef@redhat.com>,
Tomasz Chmielewski <mangoo@wpkg.org>,
linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org,
hch@infradead.org, gg.mariotti@gmail.com,
"Justin P. Mattock" <justinmattock@gmail.com>,
mjt@tls.msk.ru
Subject: Re: BTRFS: Unbelievably slow with kvm/qemu
Date: Wed, 1 Sep 2010 20:18:59 -0400 [thread overview]
Message-ID: <20100902001859.GA4930@thunk.org> (raw)
In-Reply-To: <4C7D7B14.9020008@noir.com>
On Tue, Aug 31, 2010 at 02:58:44PM -0700, K. Richard Pixley wrote:
> On 20100831 14:46, Mike Fedyk wrote:
> >There is little reason not to use duplicate metadata. Only small
> >files (less than 2kb) get stored in the tree, so there should be no
> >worries about images being duplicated without data duplication set at
> >mkfs time.
> My benchmarks show that for my kinds of data, btrfs is somewhat
> slower than ext4, (which is slightly slower than ext3 which is
> somewhat slower than ext2), when using the defaults, (ie, duplicate
> metadata).
>
> It's a hair faster than ext2, (the fastest of the ext family), when
> using singleton metadata. And ext2 isn't even crash resistant while
> btrfs has snapshots.
I'm really, really curious. Can you describe your data and your
workload in detail? You mentioned "continuous builders"; is this some
kind of tinderbox setup?
- Ted
next prev parent reply other threads:[~2010-09-02 0:18 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-29 19:34 BTRFS: Unbelievably slow with kvm/qemu Tomasz Chmielewski
2010-08-30 0:14 ` Josef Bacik
2010-08-30 15:59 ` K. Richard Pixley
2010-08-31 21:46 ` Mike Fedyk
2010-08-31 22:01 ` K. Richard Pixley
[not found] ` <4C7D7B14.9020008@noir.com>
2010-09-02 0:18 ` Ted Ts'o [this message]
2010-09-02 16:36 ` K. Richard Pixley
[not found] ` <4C7FD2AA.8090302@noir.com>
2010-09-02 16:49 ` K. Richard Pixley
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