[dpdk-dev] [PATCH v3] pipeline: add statistics for librte_pipeline

[Rajagopalan Sivaramakrishnan]

> > You also reiterate that you would like to have the stats always enabled. You
> can definitely do this, it is one of the available choices, but why not also
> accommodate the users that want to pick the opposite choice? Why force
> apps to spend cycles on stats if the app either does not want these counters
> (library counters not relevant for that app, maybe the app is only interested
> in maintaining some other stats that it implements itself) or do not want
> them anymore (maybe they only needed them during debug phase), etc?
> Jay asked this question, and I did my best in my reply to describe our
> motivation (http://www.dpdk.org/ml/archives/dev/2015-May/017992.html).
> Maybe you missed that post, it would be good to get your reply on this one
> too.
>
> I want to see DPDK get out of the config madness.
> This is real code, not an Intel benchmark special.


I agree that statistics will definitely be required in most real-world production environments and the overhead
from per-core stats gathering will be minimal if the data structures are such that CPU cache thrashing is avoided.
However, if there are scenarios where it is desirable to turn stats off, I think we can live with a config option.
I am not comfortable with using the log level to enable/disable statistics as they are not really related. A
separate config option for stats collection seems like a reasonable compromise.

Raja