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To: gnn@freebsd.org
In-reply-to: Your message of "Mon, 03 Mar 2008 15:23:33 EST."
	<7ifxv7pnei.wl%gnn@neville-neil.com> 
Date: Mon, 03 Mar 2008 13:17:31 -0800
From: Bakul Shah <bakul@bitblocks.com>
Message-Id: <20080303211731.D89A05B30@mail.bitblocks.com>
Cc: current@freebsd.org
Subject: Re: Differences in malloc between 6 and 7? 
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On Mon, 03 Mar 2008 15:23:33 EST gnn@freebsd.org  wrote:
> One of the folks I'm working with found this.  The following code,
> which yes, is just an example, is 1/2 as fast on 7.0-RELEASE as on
> 6.3.  Where should I look to find out why?

Specifying malloc option K (double virtual memory chunk size)
roughly halves the runtime.  Additional Ks reduce it more and
more.  As this test spends most of its time in the kernel,
may be this is just due to the mmap overhead? Or may be the
defaults for 6.3 were different.