sbrk(2), OOM-killer and malloc() overcommit

Vadim Goncharov vadimnuclight at
Fri Jan 4 10:32:41 PST 2008

04.01.08 @ 23:36 Tim Kientzle wrote:

> Vadim Goncharov wrote:
>> ... related "bug", in that of malloc overcommit,...
> malloc overcommit is not a bug; it's an important
> feature for many applications, for the same
> reasons that sparse files are an important feature.
> (Many applications can optimize performance by
> using an addressable region much larger than the
> actual data they need to store.)

What applications? How do they use this "feature"?

> If you really need a 4G block of memory, mmap()
> it to a file on disk.

That's not a solution for end-user. Why just not have space reserving, as  
other operating systems can guarantee to their applications that stable  
availability of memory?

WBR, Vadim Goncharov

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