<span name="katja" class="gD"></span>Excuse my ignorance:<br>not sure how to start the below version of pd on the rpi?<br><br>I have the full path but then what?<br><br>if I do (in command line)<br>pd /place/where/new/pd/is/bin/pd<br>
It signals watchdog.<br><br>I also still have regular pd 0.44.0 installed btw.<br><br>Sorry if this is dumb dumb dumb dumb Duuummmbbb.<br><br>Jb<br><br><div class="gmail_quote">On 24 January 2013 09:14, katja <span dir="ltr"><<a href="mailto:katjavetter@gmail.com" target="_blank">katjavetter@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">'Undenormalized' Pd build for Raspberry Pi is temporarily parked here<br>
for testing purposes (will be removed when Miller's release is fixed<br>
in this sense):<br>
<br>
<a href="http://www.katjaas.nl/temp/pd-0.44-0-normalized.tar.gz" target="_blank">www.katjaas.nl/temp/pd-0.44-0-normalized.tar.gz</a><br>
<br>
This is a locally installed Pd, like Miller's distribution. You can<br>
start it from command line with the full path to<br>
pd-0.44-0-normalized/bin/pd. It's not a .deb, so it can't be installed<br>
under supervision of package manager.<br>
<span class="HOEnZb"><font color="#888888"><br>
Katja<br>
</font></span><div class="HOEnZb"><div class="h5"><br>
<br>
On Wed, Jan 23, 2013 at 9:15 PM, Julian Brooks <<a href="mailto:jbeezez@gmail.com">jbeezez@gmail.com</a>> wrote:<br>
> Hey Katja,<br>
><br>
> Would you mind sharing the 'normalised' Pd-0.44.0 for RPi please.<br>
><br>
> Cheers,<br>
><br>
> Julian<br>
><br>
><br>
><br>
> On 23 January 2013 18:23, katja <<a href="mailto:katjavetter@gmail.com">katjavetter@gmail.com</a>> wrote:<br>
>><br>
>> Now I recompiled the Pd-0.44.0 release on Raspberry Pi (took me a few<br>
>> hours, not only because Pi is so slow) with PD_BIGORSMALL enabled for<br>
>> arm in m_pd.h. Using bigorsmalltest.pd from my previous mail I<br>
>> verified that the macro is implemented indeed.<br>
>><br>
>> Martin Brinkmann's patch chaosmonster1<br>
>> (<a href="http://www.martin-brinkmann.de" target="_blank">http://www.martin-brinkmann.de</a>) gives a beautiful illustration of the<br>
>> improvement. This patch is full of filters and delay lines. At it's<br>
>> initial settings, there is no subnormals problem. But if you set the<br>
>> bottom slider to the right, it gets silent. With Pd-0.44-0 release,<br>
>> CPU load explodes. With the 'normalized' Pd, nothing special happens.<br>
>><br>
>> And indeed, the PD_BIGORSMALL conditional checks come for free: with<br>
>> initial settings of the chaosmonster1, performance is equivalent in<br>
>> both Pd's. Cool! Hopefully this is similar on armv7.<br>
>><br>
>> Katja<br>
>><br>
>><br>
>><br>
>> On Wed, Jan 23, 2013 at 5:01 PM, Hans-Christoph Steiner <<a href="mailto:hans@at.or.at">hans@at.or.at</a>><br>
>> wrote:<br>
>> ><br>
>> > hey Katya,<br>
>> ><br>
>> > This also sounds like good evidence for your idea of writing C code that<br>
>> > modern compilers optimize well. Using unions for aliasing allows the<br>
>> > compiler<br>
>> > to do all the new tricks, then writing loops that auto-vectorize gives<br>
>> > us the<br>
>> > real benefits. Also, I think we can see some gains by using memcpy()<br>
>> > since on<br>
>> > modern libc version, those are highly optimized for the given CPU,<br>
>> > dynamically<br>
>> > choosing the routines based on what instructions are available. memcpy<br>
>> > will<br>
>> > use things like SSSE2 if its available.<br>
>> ><br>
>> > .hc<br>
>> ><br>
>> > On 01/23/2013 07:47 AM, katja wrote:<br>
>> >> Finally some good news on this topic. Earlier I stated that 'big or<br>
>> >> small tests' are expensive for the Pi, but that is not by definition<br>
>> >> the case. There must have been other conditions blurring my<br>
>> >> impression. I've now done a systematic test where other influences are<br>
>> >> ruled out. A test class [lopass~] with exactly the same routine as<br>
>> >> [lop~] was made, but compiled with PD_BIGORSMALL() macro enabled. It<br>
>> >> was verified that [lopass~] is not affected by denormals. Performance<br>
>> >> comparison of [lop~] and [lopass~] shows that both objects cause<br>
>> >> equivalent CPU load. Meaning, Raspberry Pi gives the 'big or small<br>
>> >> checks' for free! At least in the case of this simple filter. Please<br>
>> >> try attached bigorsmalltest.zip on the Pi to see if I'm not dreaming.<br>
>> >><br>
>> >> While I was at the topic anyway, I also tried a big or small test with<br>
>> >> union instead of direct type aliasing. It has the advantage that the<br>
>> >> compiler can apply strict aliasing rules. This test with unions did<br>
>> >> not cause extra CPU load either on the Pi. If you want to verify this<br>
>> >> result, enable the call to bigorsmall() instead of PD_BIGORSMALL in<br>
>> >> lopass~.c and recompile.<br>
>> >><br>
>> >> The fact that these tests do not cause extra CPU load, indicate that<br>
>> >> they are done in parallel with other instructions. Float and int<br>
>> >> registers are apparently strictly separated on armv6, there's no such<br>
>> >> thing like Intel's xmm registers or armv7's NEON. As it happens, the<br>
>> >> big or small tests are done on ints, aliases of the floats that must<br>
>> >> be tested. Initially I assumed that the transport of floats from vfp<br>
>> >> to the arm integer processor would be expensive, but if the<br>
>> >> instructions are done simultaneously it may be an advantage instead.<br>
>> >> Another thing is that ARM implements branch predication instead of<br>
>> >> branch prediction. Those terms look almost the same but the routines<br>
>> >> are very different. Predication is when instructions for both branches<br>
>> >> are executed, and the wrong result is simply discarded later.<br>
>> >><br>
>> >> Conclusions from the limited test with [lop~] and [lopass~] do not<br>
>> >> mean that all sorts of conditional checks are cheap on the Pi, or on<br>
>> >> ARM in general. If PD_BIGORSMALL is enabled for RPi using compile-time<br>
>> >> definition __arm__, it will also hold for armv7, but it may have very<br>
>> >> different result there. At the moment I have no access yet to an armv7<br>
>> >> device. Maybe someone can recompile test class [lopass~] and do the<br>
>> >> tests on Beagleboard or Cubieboard? Otherwise I may be able to do it<br>
>> >> on my friend's PengPod when that has arrived.<br>
>> >><br>
>> >> Katja<br>
>> >><br>
>> >><br>
>> >> On Tue, Jan 22, 2013 at 8:54 PM, Miller Puckette <<a href="mailto:msp@ucsd.edu">msp@ucsd.edu</a>> wrote:<br>
>> >>> thanks - I'd better try this and find out what's going on :)<br>
>> >>><br>
>> >>> M<br>
>> >>><br>
>> >>> On Mon, Jan 21, 2013 at 11:54:29AM +0100, katja wrote:<br>
>> >>>> Tried the 0.44.0 build from your website. It has the same issue with<br>
>> >>>> subnormal values. My test patch is with [lop~]. If inf or nan is fed<br>
>> >>>> into [lop~], these 'values' keep circulating in the object, it can no<br>
>> >>>> longer process normal signal values.<br>
>> >>>><br>
>> >>>> I also tried my reverb stuff with specific compiler options for Pi's<br>
>> >>>> processor:<br>
>> >>>><br>
>> >>>> -march=armv6zk<br>
>> >>>> -mcpu=arm1176jzf-s<br>
>> >>>> -mtune=arm1176jzf-s<br>
>> >>>><br>
>> >>>> With these options, gcc should be able to decide that RunFast mode is<br>
>> >>>> permitted. But even in combination with -ffast-math (which in turn<br>
>> >>>> sets -funsafe-math-optimizations and -fno-trapping-math amongst<br>
>> >>>> others), denormals are still there. I'm literally out of options for<br>
>> >>>> the moment. Sorry for not having better news.<br>
>> >>>><br>
>> >>>> Katja<br>
>> >>>><br>
>> >>>><br>
>><br>
>> _______________________________________________<br>
>> <a href="mailto:Pd-list@iem.at">Pd-list@iem.at</a> mailing list<br>
>> UNSUBSCRIBE and account-management -><br>
>> <a href="http://lists.puredata.info/listinfo/pd-list" target="_blank">http://lists.puredata.info/listinfo/pd-list</a><br>
><br>
><br>
</div></div></blockquote></div><br>