From: Matthew Tippett <tippettm@gmail.com>
To: kvm@vger.kernel.org
Subject: sync guest calls made async on host - SQLite performance
Date: Wed, 23 Sep 2009 11:58:54 -0400 [thread overview]
Message-ID: <4ABA45BE.1080008@gmail.com> (raw)
Hi,
I would like to call attention to the SQLite performance under KVM in
the current Ubuntu Alpha.
http://www.phoronix.com/scan.php?page=article&item=linux_2631_kvm&num=3
SQLite's benchmark as part of the Phoronix Test Suite is typically IO
limited and is affected by both disk and filesystem performance.
When comparing SQLite under the host against the guest OS, there is an
order of magnitude _IMPROVEMENT_ in the measured performance of the guest.
I am expecting that the host is doing synchronous IO operations but
somewhere in the stack the calls are ultimately being made asynchronous
or at the very least batched for writing.
On the surface, this represents a data integrity issue and I am
interested in the KVM communities thoughts on this behaviour. Is it
expected? Is it acceptable? Is it safe?
Regards,
Matthew
next reply other threads:[~2009-09-23 15:58 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-23 15:58 Matthew Tippett [this message]
2009-09-24 11:44 ` sync guest calls made async on host - SQLite performance Avi Kivity
2009-09-24 12:31 ` Matthew Tippett
2009-09-24 13:03 ` Avi Kivity
2009-09-24 19:49 ` Matthew Tippett
2009-09-25 7:22 ` Avi Kivity
2009-09-25 11:33 ` Matthew Tippett
2009-09-25 15:04 ` Avi Kivity
2009-09-29 18:58 ` Anthony Liguori
2009-09-29 18:57 ` Anthony Liguori
2009-09-29 18:54 ` Anthony Liguori
-- strict thread matches above, loose matches on Subject: below --
2009-09-25 2:11 Ian Woodstock
2009-09-25 3:13 ` Matthew Tippett
2009-09-25 7:00 RW
2009-09-27 11:37 ` Avi Kivity
2009-09-27 12:07 ` Matthew Tippett
2009-09-29 19:02 ` Anthony Liguori
2009-09-29 19:32 ` Matthew Tippett
2009-09-29 20:46 ` Dustin Kirkland
2009-09-29 20:51 ` Anthony Liguori
2009-10-07 14:15 ` Matthew Tippett
2009-10-07 16:53 ` Matthew Tippett
2009-10-07 18:59 ` Dustin Kirkland
2009-10-07 19:31 ` Matthew Tippett
2009-10-07 20:12 ` Avi Kivity
2009-10-07 21:01 ` Matthew Tippett
2009-10-09 6:05 ` Dustin Kirkland
[not found] ` <4ACE0196.9010904@gmail.com>
[not found] ` <d9c105ea0910082312n7218e1abhc69a2be660838e89@mail.gmail.com>
[not found] ` <f28b49ce0910090425p385636c3he6dfb7595927d7e4@mail.gmail.com>
2009-10-09 15:18 ` Dustin Kirkland
2009-10-09 19:06 ` Matthew Tippett
2009-10-11 9:16 ` Avi Kivity
2009-10-13 22:37 ` Christoph Hellwig
2009-10-14 11:03 ` Avi Kivity
2009-10-14 13:41 ` Christoph Hellwig
2009-10-14 16:56 ` Avi Kivity
2009-10-14 17:02 ` Christoph Hellwig
2009-10-14 22:54 ` Anthony Liguori
2009-10-14 23:37 ` Avi Kivity
2009-10-15 12:17 ` Christoph Hellwig
2009-10-15 12:36 ` Christoph Hellwig
2009-10-19 5:56 ` Avi Kivity
2009-10-13 23:08 ` Anthony Liguori
2009-10-14 2:09 ` Matthew Tippett
2009-10-14 4:12 ` Dustin Kirkland
2009-10-14 11:32 ` Matthew Tippett
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