Date: Tue, 15 Mar 2005 09:49:30 -0800
From: Brad Boyer <flar@allandria.com>
To: Linas Vepstas <linas@austin.ibm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>, akpm@osdl.org,
       linuxppc64-dev@ozlabs.org, torvalds@osdl.org,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] PPC64 iSeries: cleanup viopath
Message-ID: <20050315174929.GC10301@pants.nu>
References: <20050315143412.0c60690a.sfr@canb.auug.org.au> <0961a209ce72bb9f2a01b163aa6e6fbd@penguinppc.org> <20050316025339.318fc246.sfr@canb.auug.org.au> <20050315174310.GH498@austin.ibm.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20050315174310.GH498@austin.ibm.com>
User-Agent: Mutt/1.3.28i
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 691
Lines: 17

On Tue, Mar 15, 2005 at 11:43:10AM -0600, Linas Vepstas wrote:
> FWIW, keep in mind that a cache miss due to large structures not fitting
> is a zillion times more expensive than byte-aligning in the cpu 
> (even if byte operands had a cpu perf overhead, which I don't think 
> they do on ppc).

Actually, there is a small overhead to bytes if you make them signed.
That's why char is unsigned by default on ppc.

	Brad Boyer
	flar@allandria.com

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/