Re: [REVIEW] Re: Compression of full-page-writes - Mailing list pgsql-hackers

On 2015-03-03 08:59:30 +0900, Michael Paquier wrote:
> Already mentioned upthread, but I agree with Fujii-san here: adding
> information related to the state of a block image in
> XLogRecordBlockHeader makes little sense because we are not sure to
> have a block image, perhaps there is only data associated to it, and
> that we should control that exclusively in XLogRecordBlockImageHeader
> and let the block ID alone for now.

This argument doesn't make much sense to me. The flag byte could very
well indicate 'block reference without image following' vs 'block
reference with data + hole following' vs 'block reference with
compressed data following'.

Greetings,

Andres Freund

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