Embedded Linux Conference + Android Builders Summit

Tracing is a reliable and low-intrusiveness method to debug and optimize systems and processes. Low overhead is particularly important in embedded systems where resources and energy consumption is critical. The most advanced tracing infrastructures achieve a very low footprint on the traced software, bringing each tracepoint overhead to less than a microsecond. To reduce this still non negligible impact, the use of dedicated hardware resources is promising.In this presentation, Adrien Vergé will present alternate methods for tracing, that rely on ARM CoreSight and Intel BTS hardware modules. He will show that the time overhead for tracing can be reduced by up to four times when assisted by hardware, as compared to software tracing with LTTng, a performance oriented tracer for Linux.The proposed solutions take advantage of hardware modules present on most newer ARM SoC and Intel CPUs.