From: "Richard W.M. Jones" <rjones@redhat.com>
To: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH v3] block: Add support for Secure Shell (ssh) block device.
Date: Tue, 26 Mar 2013 14:21:39 +0000 [thread overview]
Message-ID: <20130326142139.GC26045@rhmail.home.annexia.org> (raw)
In-Reply-To: <1364294326-22155-1-git-send-email-rjones@redhat.com>
On Tue, Mar 26, 2013 at 10:38:46AM +0000, Richard W.M. Jones wrote:
> + /* According to the docs, this just updates a field in the
> + * sftp_handle structure, so there is no network traffic and it
> + * cannot fail.
> + */
> + libssh2_sftp_seek64(s->sftp_handle, offset);
While I was looking at the performance of qemu+ssh vs sshfs, I noticed
that the line above has a catastrophic effect on performance, since it
causes all readahead data to be thrown away. Ooops. I'm reworking
the patch to make seeking more intelligent.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-df lists disk usage of guests without needing to install any
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next prev parent reply other threads:[~2013-03-26 14:21 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-26 10:38 [Qemu-devel] [PATCH v3] block: Add support for Secure Shell (ssh) block device Richard W.M. Jones
2013-03-26 14:21 ` Richard W.M. Jones [this message]
2013-03-26 16:23 ` Stefan Hajnoczi
2013-03-26 17:00 ` Richard W.M. Jones
2013-03-26 19:34 ` Richard W.M. Jones
2013-03-27 6:35 ` Stefan Hajnoczi
2013-03-27 15:12 ` Anthony Liguori
2013-03-27 15:44 ` Richard W.M. Jones
2013-03-27 16:43 ` Anthony Liguori
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