optimizing & api-doc

[Lubos Lunak]

On Thursday 16 of January 2003 14:47, Alexander Kellett wrote:
> On Thu, Jan 16, 2003 at 03:18:55PM +0100, Michael Olbrich wrote:
> <skip>
>
> > From what I've seen, many speed problems within c++ programs have their
> > origin in the language. In c++ it's easy to hide complexity. This helps
> > to have a clean design, and makes the developers productive. But the
> > complexity is still there and can make the programs slow.
>
> <skip>
>
> > I think, things like this can help writing faster code while keeping it
> > simple and clean.
>
> kinda.
>
> faster code isn't so simple a phrase really. it comprises
> two things, memory usage, and algorithm optimisation. there
> are not many problems with algrms in kde due to the heavy

 I wouldn't bet on it without checking first.

> usage of qt's nice helpers such as qmaps.
>
> the other area is memory usage, that _can_ be improved from what
> i see. unfortunatley in a lot of cases it will require bic changes.
>
> memory allocations due to excessive object use and lack of zoned
> allocator usage are coming up really high in the system profiles
> i'm doing atm.
>
> are there any tools for looking at object allocation stats?

 kdesdk/kmtrace

> does kcachegrind do this sort of stuff?, i didn't have time
> over the last month to use it heavily as i've got no home system :)
>
> maybe apple's arena is slightly better than the zoneallocator?
> can some docs on the usage of the zoneallocator be written?
> or did i miss a url? ;-)

 Make sure you're using a fast malloc() implementation when playing with 
allocations. The one in current glibc versions is hopelessly slow. I wonder 
if zone allocators really make noticeable difference when having a good 
malloc implementation.

-- 
Lubos Lunak
KDE developer
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