OOM-killer prevention for master kdeinit process

[Lubos Lunak]

On Thursday 03 August 2006 10:37, Thomas Zander wrote:
> On Wednesday 2 August 2006 15:09, Lubos Lunak wrote:
> >  short summary: Out Of Memory handling on Linux sucks, KDE can suffer
> > badly from it, kernel devels are unable to do anything about it, so
> > let's again work around things ourselves.
>
> Hi Lubos.
>
> Say;  in what level does the existence of this kdeinit process depend on
> the lack of optimizations in binlib?

 What do you mean with binlib?

> And do you have the idea that we might stop using it any time soon?

 Yes, no (as in: I do, we might not). As far as speed is concerned we could 
probably have dropped kdeinit by the time prelink became somewhat usable (on 
the other hand it showed worthy even for things like the fontconfig shared 
initialization hack). But when it comes to memory relocation processing 
causes somewhere between 0,5-1M unshared memory per process (I don't remember 
the numbers exactly, but it's closer to the 1). Prelink currently only 
slightly reduces the number, -Bdirect and others won't at all, but kdeinit's 
forking and copy-on-write takes care of most of it. If you run KDE with 
KDE_IS_PRELINKED=1 the difference can be measured.

 I don't know where to draw the line, but I myself would still like to keep 
kdeinit for the time being, especially as I don't see any urging reasons to 
drop it.

> For the ones that are not following; there actually are optimizations that
> the maintainer accepted:
> http://lwn.net/Articles/192624/

 They're not _that_ big. 50% (as the subject of the linked mail says) out of a 
lot is still quite a lot. They're kind of like improving bubblesort (even 
though I'm still grateful even for them).

-- 
Lubos Lunak
KDE developer
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