Hi,
>> Here's a presentation from almost 3 years ago on
the topic, linking
>> to more recent (but still outdated)
lttng-tools/ust/modules branches
>> [1]. This approach does not require trace
synchronization at all.
>>
> Ah, cool! And thanks again.
>
> Just from a really quick look, it seems similar to
what the ftrace &
> trace-cmd developers are doing, in order to achieve
the same.
From what I saw of ftrace virtual machine tracing (my
last look at
ftrace vm tracing was more than one year ago), iirc the
guest have an
agent that sends the events to the host, who sets the
timestamp, and
that is where they are all collected. Some students did
try similar
approaches, but the one we are proposing with the lttng
branches below
still involves taking individual traces on all guests and
hosts.
>
>> The Trace Compass documentation was never updated
to link to these,
>> as I was hoping they would make it in upstream
lttng first and was
>> waiting for that. But that never happened, due to
lack of interest by
>> the community.
>>
>> If you are interested, I can try to see if I can
quickly rebase these
>> branches on the latest lttng 2.12, so you can try
it out. You could
>> also contact the lttng community to see if they
have anything in
>> their roadmap regarding this feature.
>>
> Well, if you're up for trying a quick rebase, we are
certainly up for
> giving whatever you produce a try and test it.
So I made a quick rebase, here are the branches that you
can use. I
tested very very quickly and it seems to work fine, but
don't try it in
production!
lttng-ust:
https://github.com/tahini/lttng-ust-1/tree/statedump-notifier-2.12
lttng-tools:
https://github.com/tahini/lttng-tools/tree/kvm-2.12
lttng-modules:
https://github.com/tahini/lttng-modules/tree/product_uuid
On the guests, you don't necessarily need the lttng-ust
and lttng-tools
branches, unless you want to take UST traces, just
lttng-modules is
enough there, with lttng-tools 2.12.
Additionally, for those traces to work on trace compass
Virtual Machine
analysis, you need this patch on the incubator:
https://git.eclipse.org/r/c/tracecompass.incubator/org.eclipse.tracecompass.incubator/+/122053
If you try it, please let us know how it goes!
Cheers,
Geneviève
_______________________________________________
tracecompass-dev mailing list
tracecompass-dev@xxxxxxxxxxx
To unsubscribe from this list, visit
https://www.eclipse.org/mailman/listinfo/tracecompass-dev