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Date: Mon, 28 Feb 2011 17:19:56 +0530
From: Prerna Saxena <prerna@linux.vnet.ibm.com>
Message-ID: <20110228171956.05a84fb9@zephyr>
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Subject: [Qemu-devel] [RFC][PATCH 0/2] Allow cache settings for block
 devices to be changed at runtime.
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To: qemu-devel <qemu-devel@nongnu.org>
Cc: kwolf@redhat.com, Anthony Liguori <aliguori@us.ibm.com>, Ananth Narayan <ananth@linux.vnet.ibm.com>, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

The following patchset introduces monitor commands:

1. set_cache DEVICE CACHE-SETTING
Change cache settings for block device, DEVICE, through the monitor.
(Available options : 'none', 'writeback', 'writethrough')
Eg,
(qemu)set_cache ide0-hd0 none 
-> Changes cache setting for ide0-hd0 to 'none'

2. info block
Now extended to display cache settings for available block devices.

TODOS :
-------
1. Support 'unsafe' cache mode.
2. Display current cache setting for device, if the CACHE-SETTING option
is not supplied by the user. Eg, 
(qemu)set_cache ide0-hd0
presently errors out. Ideally, it should display current cache setting 
for the given device ide0-hd0

-- 
Prerna Saxena

Linux Technology Centre,
IBM Systems and Technology Lab,
Bangalore, India