On Mon, Nov 7, 2011 at 5:35 PM, Supriya Kannery <supri...@linux.vnet.ibm.com> wrote: > On 11/07/2011 02:19 PM, Zhi Yong Wu wrote: >> >> On Mon, Nov 7, 2011 at 4:38 PM, Supriya Kannery >> <supri...@linux.vnet.ibm.com> wrote: >>> >>> On 11/04/2011 07:59 AM, Zhi Yong Wu wrote: >>>> >>>> On Sun, Oct 30, 2011 at 6:33 PM, Supriya Kannery >>>> <supri...@linux.vnet.ibm.com> wrote: >>>>> >>>>> Currently cache setting of a block device cannot be changed >>>>> without restarting a running VM. Following patchset is for >>>>> enabling dynamic change of cache setting for block devices >>>>> through qemu monitor. Code changes are based on patches >>>>> from Christoph Hellwig and Prerna Saxena. >>>>> >>>>> This patchset introduces >>>>> a. monitor command 'block_set_hostcache' using which host >>>>> pagecache setting for a block device can be changed >>>>> dynamically. >>>> >>>> I got a bit confusion. Is it used to change host pagecache setting on >>>> hyperviser or on guest? >>>> This block device said by you is for guest, right? >>>> >>> >>> This command is used for changing pagecache setting of >>> the image files in host which are acting as block devices >>> for guest. >> >> So what is the difference between it and cache option? >> > > Cache=xx sets a combination of status flags for image files > among which host pagecache is just one. Intention here is > to gradually replace cache=xx with more explicit settings > like hostcache, flush, WCE. Great, thanks. > >
-- Regards, Zhi Yong Wu