Re: Sphinx parallel build errors

[Mauro Carvalho Chehab <mchehab@kernel.org>]

Em Sun, 27 Oct 2019 11:30:22 -0700
Randy Dunlap <rdunlap@infradead.org> escreveu:

> On 10/27/19 11:17 AM, Jonathan Corbet wrote:
> > On Sun, 27 Oct 2019 11:11:57 -0700
> > Randy Dunlap <rdunlap@infradead.org> wrote:
> >   
> >>> Yes, I see oom-kills when building docs for 5.4-rc2.
> >>> But only after I ran 'gimp *.jpg' for 22 photos.
> >>>
> >>> I can see anywhere from 1 to 4 sphinx-build processes running.    
> >>
> >> I continue to have oom-kills when building docs.

My 2 cents here.

I would keep the default to use more CPUs, as nowadays I suspect that
most devs have a way more than 8GB installed. The worse machine I use
here to build Kernel is a Gen-3 i5 that has has 16GB (and it is a 
personal laptop I bought 5 years ago).

Yet, I agree that doc build should be saner on low-cap machines.

Ideally, the fix should be, IMHO, at sphinx-build: -jauto should
detect OOM possible conditions and reduce the number of used CPUs
it the max available memory is too low.

As there's now a script at Kernel, maybe the script could be modified 
to detect if the max available memory is too low, passing -j1 if,
let's say, the machine has less than (let's say) 16 GB RAM.

> >> At least 2 times I also had system freezes where I had to power
> >> cycle to reboot.

That sounds weird. I can't imagine why you would experience system
freeze with doc build. Are you sure this is not your CPU overheating?

> >>
> >> I suppose I can only hope that other people start running into this
> >> issue.  :(  
> > 
> > Are you still running gimp at the same time?  
> 
> no.
> 
> > Also, are you doing a straight "make htmldocs" or something else?  
> 
> straight "make htmldocs".


Thanks,
Mauro