Re: [RFC] kbuild: bpf: Do not run pahole with -j on 32bit userspace

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Mon, Aug 26, 2024 at 02:48:18PM -0400, Phil Auld wrote:
> On Mon, Aug 26, 2024 at 08:42:10PM +0200 Sedat Dilek wrote:
> > On Mon, Aug 26, 2024 at 7:03 PM Arnaldo Carvalho de Melo
> > <acme@kernel.org> wrote:
> > >
> > > On Mon, Aug 26, 2024 at 10:57:22AM +0200, Jiri Slaby wrote:
> > > > On 22. 08. 24, 17:24, Arnaldo Carvalho de Melo wrote:
> > > > > On Thu, Aug 22, 2024 at 11:55:05AM +0800, Shung-Hsi Yu wrote:
> > > > > I stumbled on this limitation as well when trying to build the kernel on
> > > > > a Libre Computer rk3399-pc board with only 4GiB of RAM, there I just
> > > > > created a swapfile and it managed to proceed, a bit slowly, but worked
> > > > > as well.
> > > >
> > > > Here, it hits the VM space limit (3 G).
> > >
> > > right, in my case it was on a 64-bit system, so just not enough memory,
> > > not address space.
> > >
> > > > > Please let me know if what is in the 'next' branch of:
> > >
> > > > > https://git.kernel.org/pub/scm/devel/pahole/pahole.git
> > >
> > > > > Works for you, that will be extra motivation to move it to the master
> > > > > branch and cut 1.28.
> > >
> > > > on 64bit (-j1):
> > > > * master: 3.706 GB
> > > > (* master + my changes: 3.559 GB)
> > > > * next: 3.157 GB
> > >
> > > > on 32bit:
> > > >  * master-j1: 2.445 GB
> > > >  * master-j16: 2.608 GB
> > > >  * master-j32: 2.811 GB
> > > >  * next-j1: 2.256 GB
> > > >  * next-j16: 2.401 GB
> > > >  * next-j32: 2.613 GB
> > > >
> > > > It's definitely better. So I think it could work now, if the thread count
> > > > was limited to 1 on 32bit. As building with -j10, -j20 randomly fails on
> > > > random machines (32bit processes only of course). Unlike -j1.
> > >
> > > Cool, I just merged a patch from Alan Maguire that should help with the
> > > parallel case, would be able to test it? It is in the 'next' branch:
> > >
> > > ⬢[acme@toolbox pahole]$ git log --oneline -5
> > > f37212d1611673a2 (HEAD -> master) pahole: Teduce memory usage by smarter deleting of CUs
> > >
> > 
> > *R*edzce? memory usage ...
> >
> 
> If you meant that further typo it's golden, and if not the irony is rich :)
> 
> Either way this is my favorite email of the day!

Hahaha, I went to uppercase what comes after the colon and introduced
that typo ;-)

Faxing it....

- Arnaldo