Date: Thu, 1 May 1997 07:41:55 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Michal <wapex AT silesia DOT top DOT pl>
cc: djgpp AT delorie DOT com
Subject: Re: Alignment
In-Reply-To: <3367B958.88@silesia.top.pl>
Message-ID: <Pine.SUN.3.91.970501073818.2886D-100000@is>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Precedence: bulk


On Wed, 30 Apr 1997, Michal wrote:

> I'm shure my doubles are NOT aligned on a 64 byte boundary,

They don't have to be, 32 byte alignment is all that's needed AFAIK.

> if I put a int variable beafore the inner's data I get about 10% 
> increase or decrease in performance, depending on the code and data 
> before.

I would guess that's because of the effects related to the CPU cache.  If 
you really care, you could disable the caches and see if adding an int 
variable changes anything.

But why should you care that much about 10%?  In my experience, such 
effects are highly dependant on the particular CPU and motherboard that 
you are running on, so why bother?