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2024-11-06 - 08:25

Dates and Events:

OSADL Articles:

2024-10-02 12:00

Linux is now an RTOS!

PREEMPT_RT is mainline - What's next?


2023-11-12 12:00

Open Source License Obligations Checklists even better now

Import the checklists to other tools, create context diffs and merged lists


2023-03-01 12:00

Embedded Linux distributions

Results of the online "wish list"


2022-01-13 12:00

Phase #3 of OSADL project on OPC UA PubSub over TSN successfully completed

Another important milestone on the way to interoperable Open Source real-time Ethernet has been reached


2021-02-09 12:00

Open Source OPC UA PubSub over TSN project phase #3 launched

Letter of Intent with call for participation is now available



OSADL HOWTOs

HOWTO: Latency Generator (used for calibration purposes)

Quick HOWTO

Download the file archive blocksys-0.5.tgz and type:

tar -xf blocksys-0.5.tgz
cd blocksys-0.5
make
modprobe blocksys

Then run the application

./mklatency

or, alternatively, a shell script with the same functionality

./mklatency.sh

Check out the generated latency:

tail /var/log/messages
[..]
[..] kernel: blocksys: CPU #0 will be blocked for 2000000 nops
[..] kernel: blocksys: CPU #0 blocked about 1270 us

You may then wish to check and to calibrate latency analysis tools such as cyclictest or the OSADL Latency Measurement Box by executing mklatency or mklatency.sh while these tools are running. The CYCLES constant in the mklatency.c source file and the $nops shell variable in mklatency.sh define the duration of the latency.