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Is Compass a 64-bit OS, or a 32-bit OS? #raspberrypi #pine64 #compass32 #compass64

Konrad Roeder -- WA4OSH
 

Raspberry 3 has a 64-Bit BCM2387 ARM v7 processor.  So it would make sense to compile a 64-bit image of Debian for it and modifying it for NW Digital Radio's products.  As I understand it, the current Debian Jessie derived image is a 32-bit OS.  

Check out this video to see the comparison between the 64-bit Raspberry Pi 3 and the Pine 64:
https://www.youtube.com/watch?v=ztBHACi9cqY

The real difference in the performance is due to the 32 vs 64-bit OS.

I believe that software like GNU Radio can actually run well on Raspberry Pi, if it runs the right 64-bit OS.
--Konrad, WA4OSH


Jeremy McDermond <mcdermj@...>
 


On Dec 17, 2016, at 5:00 AM, Konrad Roeder -- WA4OSH <konrad.roeder@...> wrote:

Raspberry 3 has a 64-Bit BCM2387 ARM v7 processor.

The Raspberry Pi 3 has a BCM2837 processor that implements the ARMv8 instruction set.

 So it would make sense to compile a 64-bit image of Debian for it and modifying it for NW Digital Radio's products.  As I understand it, the current Debian Jessie derived image is a 32-bit OS.  

The current image is derived from Raspbian, which is derived from Jessie.

Check out this video to see the comparison between the 64-bit Raspberry Pi 3 and the Pine 64:
https://www.youtube.com/watch?v=ztBHACi9cqY

The real difference in the performance is due to the 32 vs 64-bit OS.

It’s not a simple matter of just flipping a compiler flag and getting a 64-bit OS.  The kernel drivers for all of the BCM2837 have to be ported to the ARM64 kernel.  A bunch of this is done in the latest upstream Linux distributions, but it’s not all finished yet.  Notably the SD Card driver isn’t optimal right now.  That means that SD performance is really low and we don’t want that.

I’m continually looking at all of this, and we’ll move when it make sense.  Likely this will be when upstream Raspbian decides to move to 64-bit as well.  This is because Compass development isn’t my day job.  I don’t have time to recompile all of the literally thousands of packages in the distro and do quality control on them before release.

I believe that software like GNU Radio can actually run well on Raspberry Pi, if it runs the right 64-bit OS.

It depends on what you mean by GNU Radio “running well.”  It runs well now if you’re only doing DSP with it.  If you try to do complex graphical displays, it starts to fall down.  I’m using it for DSP work right now and it works fine.  I think the real limitation in here is the VC4 code for X Windows isn’t very mature and accelerated graphics aren’t as great as they should be.

--Konrad, WA4OSH


Jeremy McDermond

Konrad Roeder -- WA4OSH
 

Thanks for the update (and corrections).  I have a daytime job that pays the bills at well.  This in urn leaves only a few minutes for the home project ;)

--Konrad