Message-ID: <43B01390.6010206@zytor.com>
Date: Mon, 26 Dec 2005 08:00:16 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Coywolf Qi Hunt <coywolf@gmail.com>
CC: Axel Kittenberger <axel.kernel@kittenberger.net>,
       linux-kernel@vger.kernel.org
Subject: Re: Possible Bootloader Optimization in inflate (get rid of unnecessary
 32k Window)
References: <200512221352.23393.axel.kernel@kittenberger.net> <2cd57c900512251815r16422013p@mail.gmail.com>
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Coywolf Qi Hunt wrote:
>>
>>What would the optimization be worth?
>>* A faster uncompressing of the kernel, since a total 1-time memcopy of the
>>whole kernel is been optimized away.
>>* I'm not sure about the size, the memory or disk footprint. If the 32k static
>>(!) memory array in compressed/misc.c, I don't know if it safes 32k running
>>memory, or 32k on-disk size. Since I don't know the indepth working of these 
> 
> Neither for saving running memory (discarded), nor on-disk size
> (window[WSIZE] resides in BSS).
> 

I've actually implemented this for another application (where BSS was at 
a premium.)  It even has some nice benefits for code size if you do it 
right.

It indeed would avoid a cache-to-memory copy, but that's not really a 
huge deal, which is why noone has worried too much about it.

	-hpa
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