Pianotec on Odroid-N2

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ARM 32 vs. AARCH64

• CNX-Software: 64-bit ARM (Aarch64) Instructions Boost Performance by 15 to 30% Compared to 32-bit ARM (Aarch32) Instructions
• I still hope, that Modartt will provide Pianoteq sometimes compiled for AARCH64 architecture. In my opinion 32-bit code on any ARM module (Raspberry PI, Banana PI, Odroid etc.) which could also use AARCH64 code doesn't make sense. Modules which provide only ARM-32 bit architecture don't have the calculation power for Pianoteq. So why should those CPUs be supported? Canceling 32-bit support and switching to AARCH64 would be the right way....

Pianotec 6 Stage Installation on Odroid

• coming soon

Some pictures

CPU Performance Benchmarks

Benchmark by Marcos Daniel

• Github: ptq_bench.c

What the code does - description by Marcos Daniel

It is a stress test, the program generates a MIDI file with ten glissandi from the lowest A to the top C, (on white keys).
The damper pedal is down during each glissandi.
In the first try, every note takes is played 100ms after the previous one. The program asks if there was an error in the playback, 
if there is not overload, you press "y" and it will generate another MIDI file, this time with 50ms between notes.
So the sequence of notes duration is (geometric progression) 100ms, 50ms, 25ms, 12.5ms, 6.25 ms, and so on.
When the computing power is not enough, an overload will occur, let's suppose it happens whith 12.5ms of delay, then the 
next delay will be the average of 12.5ms and 25ms (the lowest time without overload) = 18.75ms, if there is not error, next 
duration will be average between this last value and the maximum time with error, i.e. (18.75 + 12.5)/2 = 15.625ms.
By doing this, quiclky one obtains a final result (10 or 12 tries), and when asked pressing key "t" (for terminate) the program exits.
Any run can be skipped by ctrl+c.
The program is "as is", and in Spanish.
At last, but not least, on odroid XU4, it run more consistentlyif you run Pianoteq (or this test) from big cores excluding small ones, 
this can be done by taskset command, in case of XU4, big cores are numbered from 4 to 7, so the command would be 
taskset 0xF0 [command]. There is some improvement if you use less niceness, for instance I ran most testst this way:
nice -10 taskset 0xF0 ./ptq_bench
Pianoteq executable file must be in the same folder and version removed, simply named "Pianoteq".

Results

• coming soon

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