Hi,
On 2013-12-03 13:03:41 +0200, Heikki Linnakangas wrote:
> The log_newpage function, used to WAL-log a full copy of a page, is missing
> the trick we normally use for full-page images to leave out the unused space
> on the block. That's pretty trivial to implement, so we should.
>
> The place where this matters the most is when building a new B-tree index.
> When wal_level > minimal, all pages in the created index are logged with
> log_newpage, and by default we leave 10% free space on index pages. So
> implementing this reduces the amount of WAL generated by index creation by
> roughly 10%.
Sounds like a good idea to me.
> Anyone see a problem with this?
I haven't looked thoroughly through all callsites, but shouldn't the
vacuumlazy callsite use std = true?
Greetings,
Andres Freund
-- Andres Freund http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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