Re: /proc/<n>/maps getting _VERY_ long

[Linus Torvalds]

In article <9kkr7r$mov$[e-mail]>,
H. Peter Anvin <[e-mail]> wrote:
>
>Do you count applications which selectively mprotect()'s memory (to
>trap SIGSEGV and maintain coherency with on-disk data structures) as
>"broken applications"?
>
>Such applications *can* use large amounts of mprotect()'s.

Note that such applications tend to not get any advantage from merging -
it does in fact only slow things down (because then the next mprotect
just has to split the thing again).

No, they aren't broken, but they should know that the use of lots of
small memory segments (even if it is a design goal) can and will slow
down page faulting, and use more memory for MM management for example. 

Linux does have a log(n) vma lookup, so the slowdown isn't huge.

		Linus