Re: [PATCH v3] tools/libxc: Batch memory allocations for PV guests

[Ross Lagerwall <ross.lagerwall@citrix.com>]

On 06/17/2015 12:14 PM, Ian Campbell wrote:
> On Mon, 2015-06-15 at 17:08 +0100, Wei Liu wrote:
>> On Mon, Jun 15, 2015 at 11:12:07AM +0100, Ross Lagerwall wrote:
>>> The current code for allocating memory for PV guests batches the
>>> hypercalls to allocate memory by allocating 1024*1024 extents of order 0
>>> at a time. To make this faster, first try allocating extents of order 9
>>> (2 MiB) before falling back to the order 0 allocating if the order 9
>>> allocation fails.
>>>
>>> On my test machine this reduced the time to start a 128 GiB PV guest by
>>> about 60 seconds.
>
>  From 61s or from 600s?

It reduced the total time _by_ 60 seconds. I think it takes about 10 
seconds to start the guest now, but it is not related to the size of 
guest memory.

Regards
-- 
Ross Lagerwall