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<div class="moz-cite-prefix"><font color="#000099">Thorin<br>
<br>
C Compiler optimization at the time of compiling Public Csound
on the ARM is a possible cause.<br>
More likely -- since Csound is highly Floating-Point intensive
-- is whether the compiler is using the ARM Hardware
Floating-Point Processor, or FPP Emulation.<br>
If only the latter for now, then simply use the INTEGER AUDIO
DATA PATHS switch in the Orchestra files, which will keep all
audio-rate signal processing in fixed-point integers, and will
be much faster than simulated floating point.<br>
<br>
This option exists in CsoundXO. Simply include "INTAUDIO" near
the top of your orchestra, before the 1st INSTR statement.<br>
The INTAUDIO switch does not exist in Public Csound, which is
probably what you are using.<br>
<br>
-- barry<br>
<br>
<br>
On 7/7/2012 2:54 PM, Sridhar Dhanapalan wrote:<br>
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cite="mid:CABPDnX=TrJXh0DHQLjJ4bPPfTz5=p+pgLy2Rs_0wkLZ8Y5u6uA@mail.gmail.com"
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<pre wrap="">CCing Barry, who may be able to shed some light on this.
Sridhar
On 6 July 2012 16:44, thorin kerr <a class="moz-txt-link-rfc2396E" href="mailto:thorin.kerr@gmail.com"><thorin.kerr@gmail.com></a> wrote:
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<pre wrap="">I've been having some trouble with Csound on the XO 1.75. A quick benchmark
test suggests performance of Csound on the 1.75 is substantially slower.
Attached are two logs of an identical test conducted on an XO 1.5 and an XO
1.75.
of note,
XO 1.5:
Elapsed time at end of performance: real: 38.003s, CPU: 37.290s
XO 1.75
Elapsed time at end of performance: real: 149.952s, CPU: 141.670s
If I were to speculate, without having looked further, my guess is csound
compilation isn't being optimised for ARM. It's causing realtime performance
problems in jam2jam, but I must admit I don't relish the task of compiling
csound myself.
Thorin
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