Re: hammer: MAP_32BIT

From: Ulrich Drepper (drepper@redhat.com)
Date: Fri May 09 2003 - 17:20:29 EST


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H. Peter Anvin wrote:
> On the other
> hand, how big of a performance issue is it really to call mmap() again
> in the failure scenario *only*?

Just look at the code, it's very expensive. In the moment the mmap code
has to sequentially look at the VMAs in question. If it fails it means
it walked the entire data structure without success. Ingo's patch does
not address this, it just makes successful allocation usually fast again.

- --
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Ulrich Drepper \ ,-----------------' \ Mountain View, CA 94041 USA
Red Hat `--' drepper at redhat.com `---------------------------
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