[Cuis] Effect of Cursor Movement

[Juan Vuletich]

Hi Folks,

(inline)

On 10/23/2015 6:10 PM, Phil (list) wrote:
> On Fri, 2015-09-11 at 13:57 -0300, Juan Vuletich wrote:
>> Hi Dan,
>>
>> (below)
>> On 9/11/2015 1:19 PM, Dan Norton wrote:
>>> Hello,
>>>
>>> To see this, Bring up BouncingAtomsMorph, enlarge the window, set a
>>> high atoms count so
>>> that you can easily sense atom movement.
>>>
>>> Notice how movement speeds up when the cursor is moved and slows
>>> when it stops? Turn
>>> on FPS. On my machine, frame rate is about 22 with no cursor
>>> movement and increases to
>>> around 36 when the cursor is moving. The cursor does not have to be
>>> in the window. It can
>>> be anywhere.
>>>
>>> Why should that be? It may not be a problem, but it is a curiosity.
>>> Any explanation?
>>>
>>> BTW this is Win7, cogwin-15.33.3427, Cuis 2478.
>>>
>>>    - Dan
>> Haven't even taken a look, so if I did maybe I would find something
>> else... but for sure Cuis is triggering MouseMoveEvents, and looking
>> for
>> possible interested parties. That, on each Morphic cycle. So, each
>> Morphic cycle might take a bit longer, and FPS can go a bit down.
>>
>> In any case, if you are curious, you can take a closer look. Often,
>> questions like this lead to possible optimizations!
>>
> The issue he's describing sounds like the opposite of that.  Any chance
> this is related to the issue we discussed on vm-dev back in 2012? (The
> thread was titled "Cog VM idling performance")  Your fix back then
> mostly addressed the issue (I've noticed some minor idling slowdowns
> since then, but nothing as extreme as when I originally reported the
> issue)

Thanks for the heads-up. You are right. The issue is related to that 
code. I fixed it, and now BouncingAtomsMorph fps is quite better and 
independent of user activity!

> Funny thing is I think I'm now dealing with the other side of this
> problem in Seaside: I have a situation where an idling VM is consuming
> too much CPU... (nothing specifically related to Cuis other than the
> warning to 'be careful of what you wish for' :-)

Check for #serverMode. This sould fix that problem. You can tweak it to 
devote very little cpu to Morphic (with sluggish Morphic when you need 
it). Squeak also has it.

Cheers,
Juan Vuletich