Re: [REVIEW] Re: Compression of full-page-writes

On 2014-09-12 22:38:01 +0300, Heikki Linnakangas wrote:
> It's worth noting that there are faster CRC implementations out there than
> what we use. The Slicing-by-4 algorithm was discussed years ago, but was not
> deemed worth it back then IIRC because we typically calculate CRC over very
> small chunks of data, and the benefit of Slicing-by-4 and many other
> algorithms only show up when you work on larger chunks. But a full-page
> image is probably large enough to benefit.

I've recently pondered moving things around so the CRC sum can be
computed over the whole data instead of the individual chain elements. I
think, regardless of the checksum algorithm and implementation we end up
with, that might end up as a noticeable benefit.

Greetings,

Andres Freund

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