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Date: Fri, 1 Feb 2002 13:29:53 -0500
From: Jeff Garzik <garzik@havoc.gtf.org>
To: Linus Torvalds <torvalds@transmeta.com>
Cc: Ingo Molnar <mingo@elte.hu>, Momchil Velikov <velco@fadata.bg>,
        Anton Blanchard <anton@samba.org>, Andrea Arcangeli <andrea@suse.de>,
        Rik van Riel <riel@conectiva.com.br>, John Stoffel <stoffel@casc.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Radix-tree pagecache for 2.5
Message-ID: <20020201132953.A27508@havoc.gtf.org>
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In-Reply-To: <Pine.LNX.4.33.0202010903060.2634-100000@penguin.transmeta.com>; from torvalds@transmeta.com on Fri, Feb 01, 2002 at 09:06:37AM -0800
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On Fri, Feb 01, 2002 at 09:06:37AM -0800, Linus Torvalds wrote:
> Even databases often use multiple files, and quite frankly, a database
> that doesn't use mmap and doesn't try very hard to not cause extra system
> calls is going to be bad performance-wise _regardless_ of any page cache
> locking.

I've always thought that read(2) and write(2) would in the end wind up
faster than mmap(2)...  Tests in my rewritten cp/rm/mv type utilities
seem to bear this out.

Is mmap(2) only preferred for large files/databases?

	Jeff



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