Re: Skip hole in log_newpage

On 2013-12-03 13:57:04 +0200, Heikki Linnakangas wrote:
> On 12/03/2013 01:37 PM, Andres Freund wrote:
> >I haven't looked thoroughly through all callsites, but shouldn't the
> >vacuumlazy callsite use std = true?
>
> Well, it's logging an empty page, ie. a page full of zeros. I'm not sure if
> you'd consider that a "standard" page. Like the backup-block code in xlog.c,
> log_newpage actually makes a full page image without the hole if pd_lower ==
> 0, even if you pass std = 'true', so the end result is the same.

Hm. It should have been PageInit()ed and thus have sensible
pd_lower/upper, right? Otherwise we'd have entered thePageIsNew() branch
above it.
It's obviously not critical, but it seems like a shame to write 8kb when
it's not necessary.

Greetings,

Andres Freund

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Andres Freund http://www.2ndQuadrant.com/
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