konqy preloading kills performance

[Alexander Neundorf]

On Tuesday 14 December 2004 21:20, kfm-devel-request at kde.org wrote:
> What makes me think that the problem is not related to the memory used by
> shared libraries, is the 3rd line:
> 08052000 (46784 KB)    rwxp (00:00 0)      
>
> Is this shared memory?
>
> A "fresh" konqueror seems, in fact, to show a different number:
> 0804a000 (3440 KB)     rwxp (00:00 0)
>
> And the last line of the output is:
> mapped:   32096 KB writable/private: 4996 KB shared: 1072 KB
>
>
> I hope these numbers can be useful.
>
> Cheers,
>         Dario

My guess: lots of tabs, lots of pictures opened at once, many big 
html-structures at once -> high peak memory requirements.
The dlmalloc sources say 
" If possible, gives memory back to the system (via negative
  arguments to sbrk) if there is unused memory at the `high' end of
  the malloc pool."

I have the impression that usually this doesn't happen, there are probably in 
most cases still some used chunks at the high end of the malloc pool.
My (slackware 9.1) sbrk manpages says: 
"sbrk increments the program's data space by increment bytes. sbrk isn't a 
system call, it is just a C library wrapper. Calling sbrk with an increment 
of 0 can be used to find the current location of the program break."
It doesn't talk about giving memory back.

Giving precise numbers for the performance is quite hard. I mean due to the 
swapping even konsole has to swap back in when it gets focus. How should I 
measure this in numbers ?

Bye
Alex
-- 
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