Tag: standard kernel

• #Raspberry Pi: The N-queens Problem (benchmark) Preempt-RT vs. Standard Kernel

  Real Time Systems | 5 min | 13718

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  raspberry pi

  preempt-rt

  standard kernel

  performance

  n-queen problem

  N-Queens Problem: A Benchmarking Solver for Raspberry Pi

  The N-Queens Problem/Puzzle is a well-known problem that consists of placing N chess queens on an N × N chessboard so that no two queens attack each other. For example, one possible solution to the N-queens problem for N = 4 is the following:

  Fig. 1: N-queens problem example (N = 4). Source: Google Optimization Tools

  As you can see, there aren't two queens on the same row, column or diagonal. Usually t...

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• #Raspberry Pi: Preempt-RT vs. Standard Kernel 4.14.y

  Real Time Systems | 5 min | 18359

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  raspberry pi

  kernel patching

  standard kernel

  preempt-rt kernel

  latency

  performance

  The last week I was working on a real-time application (with a 1 ms sample time) that runs on an ARMv8 Cortex-A53 (Raspberry Pi 3 Model B based board) and I was wondering the differences between latencies on the standard and the Real-Time (RT) Linux kernel. I had some problems with the standard kernel version, then I thought I could analyze the latencies of both kernels, and make some conclusions. Many test are available but with older kernel versions. The tests were perfo...

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• #Raspberry Pi: Preempt-RT Patching Tutorial for Kernel 4.14.y

  Real Time Systems | 6 min | 43591

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  raspberry pi

  kernel patching

  raspbian

  preempt-rt

  standard kernel

  You can still read this article, but a new tutorial is available here:

  Preempt-RT Patching Tutorial - Raspberry Pi

  There are a lot of tutorials for Raspberry Pi kernel patching using Preempt-RT, but I needed about 15 hours to get it working! I hate Kernel patching! and I have to say, that's not my first time. I have a system working with Ubuntu, RTAI and an Ethercat master. I patched the system more than once. But it is/was always a new thing! and It costs a lot of tim...

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