Re: [patch] remove vcpu_info array v5

Glauber Costa
2008-11-12T13:09:28Z

On Wed, Nov 12, 2008 at 11:02 AM, Jes Sorensen <jes@sgi.com> wrote:
> Avi Kivity wrote:
>>
>> Jes Sorensen wrote:
>>>
>>> What I meant was that I was able to compile the code, and there was only
>>> one piece left that needed that function, which is why I moved it and
>>> made it static in the acpi code.
>>>
>>
>> That's because there is another static array in acpi.c...
>
> Which array are you talking about? ACPI has it's own limitations, like
> we need ACPI 3.0 to go beyond 256 processors :-(
>
>>> Well we have to start somewhere. Just because there's limits in other
>>> areas too, doesn't mean we should discard valid improvements elsewhere.
>>> I'll get to some of that at some point, but there's soo many cards used
>>> to build this house....
>>
>> Your patch builds the 16383rd floor while ignoring the 15th. Qemu scaling
>> issues are much, much more painful than what you were addressing.
>
> Well I am not ignoring the 15th floor, I am just putting in expandable
> rails that can go all the way to the 16383rd. Next I'll get to look at
> putting in the button to make the elevator stop at the 15th+ floors :)
>
> Cheers,
> Jes
>
I think the main point here is that currently, one of the showstopers
for scalability,
is the lack of fine grained locking. And we don't really know how the
code will look like
after that. It can very well change completely, rendering this work as
totally void.

--
Glauber Costa.
"Free as in Freedom"
http://glommer.net

"The less confident you are, the more serious you have to act."