From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: [PATCH] 3% tighter packs for free
Date: Fri, 17 Mar 2006 23:21:33 -0800
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To: Nicolas Pitre <nico@cam.org>
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	Pitre's message of "Fri, 17 Mar 2006 22:45:07 -0500 (EST)")
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Nicolas Pitre <nico@cam.org> writes:

>  			if (inscnt) {
> +				while (moff && ref_data[moff-1] == data[-1]) {
> +					if (msize == 0x10000)
> +						break;
> +					/* we can match one byte back */
> ...
> +					break;
> +				}
>  				out[outpos - inscnt - 1] = inscnt;

Once you make it into a patch form, it is plainly obvious that
this is a good optimization.  Since our BLK_SIZE is 16 bytes,
you are grabbing up to 15 more bytes (on average 8 more bytes or
so) for every match after a partially modified block.

Very nice.  I wonder if a larger BLK_SIZE (say 32 bytes) would
give us faster packing without losing much compression if we use
this idea.