Raspberry PI 4: CPU too powerful/memory too slow?

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sadko4u
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Raspberry PI 4: CPU too powerful/memory too slow?

Post by sadko4u »

I'm currently profiling some DSP code that I try to optimize for Raspberry Pi 4.
The most interesting thing related to Raspberry PI 4 is that SIMD-optimized code gets nearly the same performance as same scalar code.
Currently looking with the perf tool, I see the bottleneck related to the... memory???
Here's a screenshot:
Image
Last edited by sadko4u on Mon Dec 09, 2019 1:21 pm, edited 1 time in total.
LSP (Linux Studio Plugins) Developer and Maintainer.

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sadko4u
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Posts: 757
Joined: Mon Sep 28, 2015 9:03 pm

Re: Raspberry PI 4: CPU too powerful?

Post by sadko4u »

As the opposite situation, here's the same code for Raspberry Pi 3B+
Image
As we see here, there are less losses on load/store instructions than for Raspberry Pi 4B
LSP (Linux Studio Plugins) Developer and Maintainer.

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