[Vm-dev] Cog VM idling performance

Igor Stasenko siguctua at gmail.com
Thu Jun 7 03:36:01 UTC 2012


On 7 June 2012 03:37, Phil (list) <pbpublist at gmail.com> wrote:
>
> Igor,
>
> On Jun 6, 2012, at 2:24 PM, Igor Stasenko wrote:
>
>>
>> just kill an idle process.
>> but you must be sure that at any moment of time there will be some
>> scheduled process
>> available, otherwise VM will leave to OS, since it will unable to find
>> anything to run
>>
>
> I'm not sure I understand: I have a morph with stepping enabled (every 50ms)... shouldn't that keep the idle process from taking over?  If not (i.e. and your suggestion is the way to go), what's the recommended way to kill the idle process and how would I restart it when I no longer want maximum performance?

no.. when you say 'every 50ms' this means that your process will awake
every 50ms
but rest of the time it will put oh hold ==>> means nothing to do for
VM during these 50ms.
actually, morphic world default inter-cycle pause is 20ms..
but this doesn't changes the fact that when UI process is on hold,
then scheduler
scheduling idle process, which tells VM to relinquish CPU to OS.
an idle process is always scheduled at minimum possible priority (like
that, scheduler always can find a process which must be scheduled).

>
> The link to the image I posted in my reply to Bert will also display the behavior I'm describing: simply moving the mouse around while the stepping is active will increase the framerate, when you stop moving the mouse it decreases.
>
you can play with #interCyclePause: in morphic to see if problem is there.
because idle process pausing VM for 1ms.. this is too small to affect
frame rate.

>> --
>> Best regards,
>> Igor Stasenko.


-- 
Best regards,
Igor Stasenko.


More information about the Vm-dev mailing list