[lttng-dev] babletrace2 graph performance considerations

[simark@simark.ca (Simon Marchi)]

On 2020-03-30 1:30 p.m., Rocky Dunlap wrote:
> In my case I have CTF trace where some analyses can be performed on a per-stream basis (no need to mux the streams together).? In this case, I was thinking that it would make sense to thread over the streams.? However, I think can easily do this at a level above the graph simply by creating multiple graphs where each one is handling a single stream.? In my case I am thinking this will be mostly I/O bound, so I'm not sure what kind of payoff the threads will give.? Overall, I just want to make sure that I am not doing anything that would, in the long run, preclude threading/concurrency if it is added to the graph model itself.

Creating multiple graphs and handling a single stream in each would
work, but each graph would end up reading and parsing the while CTF
trace, which is not great.

If you streams are in a data file of their own, you could move them
to their own directory, each with a copy of the metadata, effectively
creating one trace for each.  Then create one graph for each trace.

I can't really tell you right now how to design your components to work
with a future model where there is concurrency, since that model does
not exist yet :).

Simon