I think the power-of-two issue is only to do with
full-duplex on portaudio.

Victor
----- Original Message ----- 
From: "Steven Yi" 
To: 
Sent: Tuesday, January 13, 2009 6:31 PM
Subject: [Csnd] Re: Re: Re: SR and CPU Usage on the OLPC?


> Hi Art,
>
> Would you also try power-of-two for ksmps?  Maybe try 16, 32, and 64?
> I don't remember exactly but there was a thread a long time ago that
> suggested using power-of-two for ksmps yielding better results; I'm
> not sure if I'm remembering that correctly or not, but I've been
> following that for a while now.
>
> Thanks!
> steven
>
> On Tue, Jan 13, 2009 at 9:51 AM, Art Hunkins  wrote:
>> Victor,
>>
>> Thanks for this very helpful observation. It led to the solution to my
>> problem. It indeed turns out that the control rate is considerably more
>> important than SR in regard to CPU usage.
>>
>> Data:
>> SR=44100, ksmps=10: csound CPU usage=98, overall CPU usage=95
>> SR=36000, ksmps=10: csound CPU=61, overall CPU=71
>> SR=36000, ksmps=100: csound CPU=4, overall CPU=5
>>
>> The latter is a *dramatic* difference - one I can live with. Finally,
>> "sensekey tamed."
>>
>> (Any explanations greatly appreciated.)
>>
>> Thanks again, Victor.
>>
>> Art Hunkins
>>
>> ----- Original Message ----- From: "victor" 
>> To: 
>> Sent: Tuesday, January 13, 2009 3:57 AM
>> Subject: [Csnd] Re: SR and CPU Usage on the OLPC?
>>
>>
>>> I also noticed that changing the control rate also makes
>>> a great deal of difference.
>>>
>>> Victor
>>> ----- Original Message ----- From: "Art Hunkins" 
>>> To: 
>>> Sent: Tuesday, January 13, 2009 3:40 AM
>>> Subject: [Csnd] SR and CPU Usage on the OLPC?
>>>
>>>
>>>> Does anyone have an explanation for the following bizarre (but 
>>>> verified)
>>>> data regarding SR's and CPU usage on the OLPC? My test .csd is with
>>>> ksmps=10, realtime, with MIDI input.
>>>>
>>>> SR=44100: Csound CPU usage = 26%, total CPU usage = 54%
>>>> (SR=48000: 32% and 52%)
>>>> SR=36000: 4% and 6%
>>>> SR=32000: 3% and 5%
>>>> SR=22050: <3% and 4%
>>>>
>>>> All conditions, to my knowledge, except for SR, were identical.
>>>>
>>>> It makes no sense to me, but the difference is real. I'll be using
>>>> SR=32000 or 36000 instead of 44100.
>>>>
>>>> Whatever the reason, I'll now be able to port *some* of what I'd hoped 
>>>> to
>>>> the OLPC.
>>>>
>>>> Art Hunkins
>>>>
>>>>
>>>> Send bugs reports to this list.
>>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body 
>>>> "unsubscribe
>>>> csound"
>>>
>>>
>>>
>>> Send bugs reports to this list.
>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>> csound"
>>
>>
>>
>> Send bugs reports to this list.
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>> csound"
>>
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe 
> csound"