Re: [Qemu-devel] [PATCH] qed: replace vm_clock with rt_clock for qemu-tool compatibility

[Stefan Hajnoczi]

On Mon, Feb 27, 2012 at 2:20 PM, Zhi Yong Wu <address@hidden> wrote:
> On Sun, Feb 26, 2012 at 10:55 PM, Stefan Hajnoczi
> <address@hidden> wrote:
>> The QED dirty bit timer marks the file clean after allocating writes
>> have drained.  This is cheaper than clearing/setting the dirty bit on
>> each allocating write because the timer introduces a grace period which
>> can be extended if more allocating writes arrive.
>>
>> The vm_clock was used in an attempt to prevent modifying the image file
> Why can vm_clock do this work but other clock can not? If you're
> available, can you elaborate what the difference among the three
> clocks is? such as vm_clock, rt_clock, and host_clock.

See qemu-timer.h.

Stefan