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Changing clock period (ticksize) in QNX 8   ________________________________________________________________________ Applicable Environment ________________________________________________________________________ Topic: ClockPeriod() change in QNX 8 SDP: 8.0.0 Target: AArch64, x86_64 ________________________________________________________________________ Issue ________________________________________________________________________ On QNX 7.1 (and previous versions) the timer granularity (ticksize) can be changed with the ClockPeriod() "new" argument. This argument is not used in QNX 8.0 any more. ________________________________________________________________________ Recommendation ________________________________________________________________________ Changing the clock period has been moved from a dynamically configurable value, which could cause problems for applications, to a system-wide configuration. Instead of using the ClockPeriod() "new" argument you can get timers with higher precision by Changing clock frequency by using the procnto* -C tick_frequency [,clock_IST_priority] option. Using high-resolution timers. Please refer to the release notes for additional details. Note: Since timers are now tracked and handled on the core where the thread makes its timer_settime() configuration call, if you hit the 50 event expiration limit, distributing the threads using timers across cores with core affinity will distribute the timer handling across cores (but you need to do your core affinity before setting up your timer), and give all threads better latency when multiple threads have a timer expire at the same time. ________________________________________________________________________ NOTE: This entry has been validated against the SDP version listed above. Use caution when considering this advice for any other SDP version. For supported releases, please reach out to QNX Technical Support if you have any questions/concerns. ________________________________________________________________________ Related Attachments  None Found

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