Re: [PATCH] allow vma merging with mlock et. al.

[Chris Wright <chrisw@osdl.org>]

* Andrea Arcangeli (andrea@suse.de) wrote:
> The object of the merge is to save memory, and to reduce the size of the
> rbtree that might payoff during other operations (with a smaller tree,
> lookups will be faster too). If you only measure the time of creating
> and removing a mapping then it should be normal that you see a slowdown
> since merging involves more work than non-merging. The payoff is
> supposed to be in the other operations.

I agree, that test is pathological worst case.

> The reason mlock doesn't merge is that nobody asked for it yet, but it
> was originally supposed to merge too (I stopped at mremap since mlock
> wasn't high prio to fixup). But the long term plan was to eventually add
> merging to mlock too and it's good that you're optimizing it now.

Do you support merging this patch?  Or did you mean further optimizations?

thanks,
-chris
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