Re: Profiling support?

From: David Kastrup <dak@gnu.org>
Date: Feb 16, 2014, 15:59 UTC
Message-ID: <871tz3xd3d.fsf@fencepost.gnu.org>
In-Reply-To: <87wqgv2hag.fsf@thomasrast.ch>

Thomas Rast <tr@thomasrast.ch> writes:

Show 12 quoted lines

> David Kastrup <dak@gnu.org> writes:
>
>> Looking in the Makefile, I just find support for coverage reports using
>> gcov.  Whatever is there with "profile" in it seems to be for
>> profile-based compilation rather than using gprof.
> [...]
>> Is there a reason there are no prewired recipes or advice for using
>> gprof on git?  Is there a way to get the work done, namely seeing the
>> actual distribution of call times (rather than iterations) using gcov so
>> that this is not necessary?
>
> No reason I'm aware of, other than that nobody ever wrote it.

A solid testing/benchmarking framework would quite seem like a useful GSoC project as it would make it easy for casual programmers to dip their feet into their personal bottlenecks, and it would make it much easier to find worthwhile hotspots for future projects taking the challenge of speeding up core and/or specific operations.

> Note that I wouldn't exactly be surprised if the gcov targets had
> bitrotted without anyone noticing.  I haven't heard of any heavy users.
> I originally wrote them to do some basic test coverage analysis, but
> that's about it.

I've managed to make use of the outer sandwich layers: the prepare and the evaluate stuff. I ran my own tests for benchmarking though.

It's enfuriatingly hard to get the stuff in the right directories and with the right options, so that was already more helpful than it probably should have been.

-- 
David Kastrup