Re: [PATCH next v4 0/5] minmax: Relax type checks in min() and max().

[Stephen Rothwell <sfr@canb.auug.org.au>]

[-- Attachment #1: Type: text/plain, Size: 1427 bytes --]

Hi Linus,

On Mon, 8 Jan 2024 13:11:12 -0800 Linus Torvalds <torvalds@linux-foundation.org> wrote:
>
> Whee.

Yeah.

> On my machine, that patch makes an "allmodconfig" build go from
> 
>     10:41 elapsed
> 
> to
> 
>      8:46 elapsed
> 
> so that min/max type checking is almost 20% of the build time.
> 
> Yeah, I think we need to get rid of it.
> 
> Can somebody else confirm similar time differences? Or is it just me?

I was hopeful, but:

no patch:

$ /usr/bin/time make ARCH=x86_64 CROSS_COMPILE=x86_64-linux-gnu- -j140 -O -s
102460.07user 3710.56system 13:29.05elapsed 13122%CPU (0avgtext+0avgdata 4023168maxresident)k
304inputs+7917056outputs (1998673major+120730959minor)pagefaults 0swaps

with patch:

$ /usr/bin/time make ARCH=x86_64 CROSS_COMPILE=x86_64-linux-gnu- -j140 -O -s
99775.75user 3684.45system 13:12.89elapsed 13048%CPU (0avgtext+0avgdata 2217536maxresident)k
64inputs+7890304outputs (2104371major+119837267minor)pagefaults 0swaps

$ x86_64-linux-gnu-gcc --version
x86_64-linux-gnu-gcc (Debian 13.2.0-7) 13.2.0
$ lscpu
Architecture:           ppc64le
  Byte Order:           Little Endian
CPU(s):                 160
  On-line CPU(s) list:  0-159
Model name:             POWER9, altivec supported
  Model:                2.2 (pvr 004e 1202)
  Thread(s) per core:   4
  Core(s) per socket:   20
  Socket(s):            2

-- 
Cheers,
Stephen Rothwell

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 488 bytes --]