[lttng-dev] LTTng and containers.

[Maksim Khmelevskiy via lttng-dev]

Hi,

I would like to ask regarding the hot topic - container tracing. I've seen
a youtube video , have read a
message 
from LTTng mailing list and tried to google more about this topic but
didn't find much of info. Could you please direct me where should I
continue digging?
My problem:
I would like to have multiple containers where traces are generated by apps
with compiled-in tracepoints. Traces could be stored in these containers as
well.
Besides these containers I would have a trace processor container, a master
container which could address a container(or a trace session) and fetch
traces from it and read with babeltrace or similar tool.
So far, intuitively, remote tracing comes to my mind but before continuing
with the task I would be happy to hear an advice from LTTng devs.

Thank you!
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[lttng-dev] lttng-ust on arm64 getting bogged down by the getcpu syscall (taking more than 600ns per call)

[Akhil Veeraghanta via lttng-dev]

Hello!

I've run into an issue with getcpu not having a vsdo implementation and taking 
anywhere from 600ns to 80us (avg 1 us) when using lttng-ust tracepoints.
I am on lttng v2.13 and kernel version 4.9.253-l4t, running on a jetson 
(arm64). I was digging around and found that rseq might be the recommended next 
step

I am wondering:

  1.  Are there examples of using rseq system call to replace getcpu
  2.  Are there any existing patches that I can apply to get better getcpu 
performance

Thanks in advance,
Akhil
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