Re: [gentoo-user] per package parallel build

[Neil Bothwick]

On Tue, 3 Dec 2019 16:26:58 -0500, John Blinka wrote:

> > But if you emerge --update libreoffice before the package that is
> > forcing the rebuild, why would libreoffice rebuild? I would expect it
> > to only rebuild libreoffice after the dependency had been changed.
>
> That’s exactly what happened.  I issued an emerge -DuNv —changed-deps
> libreoffice first.  That had the effect of 1) first upgrading several
> libreoffice dependencies, and 2) subsequently rebuilding libreoffice
> once the dependencies changed.  I’m guessing emerge is smart enough to
> trigger both activities and sequence them appropriately.  Operative
> word is guess - I don’t pretend to understand the inner workings.

That's good to know - that it works, i mean, not that you don't
understand how ;-)
>
> > I'm not saying out wouldn't work some of the time, but I can see
> > situations where it wouldn't. Whereas
> >
> > emerge --opts @world --exclude memory-hogs...
> > emerge --opts --jobs 1 @world
> >
> > should always isolate them.
>
> Agreed that this technique should always work.  And it has the
> advantage of fewer invocations of emerge.  But at the cost, I suspect,
> of serializing the building of any memory hog dependencies that were
> excluded from consideration by the first invocation of emerge.

That's a fair point, but it would only apply if the hog had a new
dependency. Even then, it would only be significant if the dependency was
large.

> What situations do you see as not working?

The ones I mentioned before, but it seems that portage may be intelligent
to deal with them. It will be interesting to see if it continues to work
over time.


-- 
Neil Bothwick

Q: Why do PCs - even modern ones - have reset buttons on the front?
A: Because they come with Microsoft operating systems.