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Date: Sun, 26 Oct 2003 01:02:38 -0500 (CDT)
From: Mike Silbersack <silby@silby.com>
To: David Schultz <das@FreeBSD.ORG>
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Subject: Re: Some mmap observations compared to Linux 2.6/OpenBSD
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On Sat, 25 Oct 2003, David Schultz wrote:

> But regardless of the approach, someone has yet to demonstrate
> that this is actually a performance problem in the real world. ;-)

I could be way wrong, but I would think that a database might mmap
discontiguous segments of memory.  Perhaps someone familiar with
mysql/postgres/others might know if they would be a good benchmark.

Actually, relating to this, didn't phk request a VM function which would
remap a page (or contiguous segment of pages) to a new address which had
free space after it?  I believe that he needed such a feature to
turbocharge realloc().  It sounds like the freelist mode of operation
would make that more feasible.

Mike "Silby" Silbersack