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2024-03-29 - 13:06

Dates and Events:

OSADL Articles:

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



"Latest Stable" main page - Criteria - Examples

Examples

Stability regression - Latency regressions

Stability regression

The following 1-year recordings of uptime and kernel version have been obtained on a VIA EPIA-V board that is equipped with a CentaurHauls VIA Samuel 2 CPU running at 533 MHz.

Further analysis

There is little doubt that this instability with an average uptime of about 10 days was introduced when upgrading from version 2.6.33.9-rt31 to 3.2.2-rt10. Apparently, the upgrade to version 3.2.23-rt37 did not help.

In order to relate the crashes to certain external conditions, we regularly carry out host alert histogram analyses with respect to day of the month, day of the week and hour of the day:

Day of the month

Day of the week

Hour of the day

Unfortunately, the histogram analyses do not provide any hint towards the origin of the crashes in this particular case, since no time clusters of the crash times can be established.

Conclusion

An instability of unknown origin was introduced when upgrading from the 2.6.x to the 3.x kernel series. Since the system does not produce any output when crashed – even not when forced using a SysRq command – specific hardware instrumentation may be required to elucidate the origin of this instability.