Re: Performance Patches Was: Lock Wait Statistics (next commitfest)

[Robert Haas <robertmhaas(at)gmail(dot)com>]

On Sat, Feb 27, 2010 at 6:22 PM, Mark Kirkwood
<mark(dot)kirkwood(at)catalyst(dot)net(dot)nz> wrote:
> Greg Smith wrote:
>> While I was in there I also added some more notes on my personal top patch
>> submission peeve, patches whose purpose in life is to improve performance
>> that don't come with associated easy to run test cases, including a sample
>> of that test running on a system that shows the speedup clearly.  If I were
>> in charge I just would make it standard project policy to reject any
>> performance patch without those characteristics immediately.
>
> While I completely agree that the submitter should be required to supply a
> test case and their results, so the rest of us can try to reproduce said
> improvement - rejecting the patch out of hand is a bit harsh I feel - Hey,
> they may just have forgotten to supply these things! The reviewer can always
> ask, can they not? I would prefer to see the wiki say something along the
> lines of "If you don't supply a test case you will be asked for one before
> any further review can proceed..."

Agreed.  Personally, I have no problem with giving a patch a brief
once-over even if it lacks an appropriate test case, but serious
review without a test case is really hard.  That's one of the things
that slowed down rbtree a lot this last CommitFest.  We should
probably try to make a point of trying to point this problem out to
patch submitters before the CommitFest even starts, so that they can
address it in advance.

...Robert