Re: Linux 2.4.2 fails to merge mmap areas, 700% slowdown.

[Jakob Østergaard <jakob@unthought.net>]

On Tue, Mar 20, 2001 at 10:43:33AM -0800, Linus Torvalds wrote:
> 
> 
> On Tue, 20 Mar 2001, Serge Orlov wrote:
> >
> > I upgraded one of our computer happily running 2.2.13 kernel
> > to 2.4.2. Everything was OK, but compilation time of our C++
> > project greatly increased (1.4 times slower). I investigated the
> > issue and found that g++ spends 7 times more time in kernel.
> > The reason for this is big vm map:
> 
> Cool. Somebody actually found a real case.
> 
> I'll fix the mmap case asap. Its' not hard, I just waited to see if it
> ever actually triggers. Something like g++ certainly counts as major.

Uber-cool !  :)

> 
> Are you willing to test out patches?

Definitely.

-- 
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:   jakob@unthought.net   : And I see the elder races,         :
:.........................: putrid forms of man                :
:   Jakob Østergaard      : See him rise and claim the earth,  :
:        OZ9ABN           : his downfall is at hand.           :
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