====== Title: RT troubles, lessons learned, and open questions ======

Saturday, October 21, 2017 • 9:20 - 10:10

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===== Abstract =====
Over the years of using PREEMPT_RT, at National Instruments, we have
managed to run into some of its trouble spots. This presentation will
summarize some of our woes, lessons learned and open up a discussion
about possible solutions.

Possible topics for discussion:

  * timer expirations coming from low priority threads can introduce large latencies for RT threads waiting on a timer expiration;
  * stalls when doing multiple PCI/PCIe MMIO writes followed by a read;
  * migration events can stack up to large latencies;
  * CPU prefetching into memory regions mapped over slow buses can cause latency spikes.

===== Audience =====
RT users and developers.


===== Biography =====
====Gratian Crisan, National Instruments====

Gratian has been playing around with Linux since 1999 among other
embedded and real-time OSes. He is currently employed by National
Instruments on the RT OS team, working almost exclusively with Linux
and PREEMPT_RT.

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