Re: [Qemu-devel] vga optmization

["Glauber Costa" <glommer@gmail.com>]

On Tue, Nov 4, 2008 at 12:51 PM, Avi Kivity <avi@redhat.com> wrote:
> Stefano Stabellini wrote:
>>
>> Why don't you make qemu_physical_sync_dirty_bitmap take also and end
>> address, and you merge the two bitmaps in this address range in this
>> function, so you don't have to change cpu_physical_memory_get_dirty at
>> all?
>>
>> I am saying to do something like:
>>
>> void qemu_physical_sync_dirty_bitmap(ram_addr_t start_addr, ram_addr_t
>> end_addr)
>> {
>>        /* sync and merge the two bitmaps between start_addr and end_addr
>> */
>> }
>>
>> then leave cpu_physical_memory_get_dirty untouched.
>> I would prefer this approch, it also leaves more space to other
>> optimizations.
>>
>
> That's how current kvm userspace works.  It's also more correct, since the
> kvm bitmap feeds both the vga dirty bits and the live migration dirty bits.

My reason to do this way, was to be lazy about updating the dirty bitmap.
But if the common case is to check for all pages in the region, then
it won't matter much.

>
> --
> error compiling committee.c: too many arguments to function
>
>
>
>



-- 
Glauber  Costa.
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http://glommer.net

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