Re: Block-level CRC checks

* Heikki Linnakangas:

> Currently, hint bit updates are not WAL-logged, and thus no full page
> write is done when only hint bits are changed. Imagine what happens if
> hint bits are updated on a page, but there's no other changes, and we
> crash so that only one half of the new page version makes it to disk
> (= torn page). The CRC would not match, even though the page is
> actually valid.

The non-logged hint bit writes are somewhat dangerous anyway.  Maybe
it's time to get rid of this peculiarity, despite the performance
impact?

--
Florian Weimer                <fweimer@bfk.de>
BFK edv-consulting GmbH       http://www.bfk.de/
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