linux-kernel - RE: [PATCH] add slice by 8 algorithm to crc32.c

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Date:	8 Aug 2011 16:45:24 -0400
From:	"George Spelvin" <linux@...izon.com>
To:	joakim.tjernlund@...nsmode.se, linux@...izon.com,
	rpearson@...temfabricworks.com
Cc:	akpm@...ux-foundation.org, fzago@...temfabricworks.com,
	linux-kernel@...r.kernel.org
Subject: RE: [PATCH] add slice by 8 algorithm to crc32.c

> Happy to consider this. I have been asking the list for comments about the
> idea of dropping the BITS=2 and BITS=4 algorithms altogether which would
> make the table size just 256. So far no one has claimed that they actually
> care about those algorithms except as 'examples'. The 'Sarwate' algorithm
> (which I added as an 8 bit version) is faster and only adds 2x4KB of table.

Um, I thought the Sarwate agorithm was what was already there as BITS=8.
(The original paper stores the CRC in two 8-bit variables and two
8-bit tables rather than using 16-bit words, but other than that,
it's identical.)

And that requires just 1KB of table per endianness.

Anyway, I thought the complaint about laarge tables was
not so much the memory as the L1 cache pollution.
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