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Re: [Qemu-devel] [PATCH v3] block: Add support for Secure Shell (ssh) bl
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From: |
Richard W.M. Jones |
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Subject: |
Re: [Qemu-devel] [PATCH v3] block: Add support for Secure Shell (ssh) block device. |
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Date: |
Tue, 26 Mar 2013 14:21:39 +0000 |
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User-agent: |
Mutt/1.5.20 (2009-12-10) |
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.
--
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