Re: Speed up clean meson builds by ~25%

On 19.05.24 00:09, Andres Freund wrote:
> On 2024-05-18 00:35:08 +0200, Peter Eisentraut wrote:
>> I retested the patch from 2024-04-07 (I think that's the one that "fixed
>> that"?  There are multiple "v1" patches in this thread.) using gcc-14 and
>> clang-18, with ccache disabled of course.  The measured effects of the patch
>> are:
>>
>> gcc-14:   1% slower
>> clang-18: 3% faster
>>
>> So with that, it doesn't seem very interesting.
> I wonder whether the reason you're seing less benefit than Jelte is that - I'm
> guessing - you now used ninja 1.12 and Jelte something older.  Ninja 1.12
> prioritizes building edges using a "critical path" heuristic, leading to
> scheduling nodes with more incoming dependencies, and deeper in the dependency
> graph earlier.

Yes!  Very interesting!

With ninja 1.11 and gcc-14, I see the patch gives about a 17% speedup.