Re: [HACKERS] GSoC 2017: weekly progress reports (week 6)

Teodor Sigaev wrote:
> 
> Alvaro Herrera wrote:
> > I don't quite understand the new call in gininsert -- I mean I see that
> > it wants to check for conflicts even when fastupdate is set, but why?
> If fastupdate is set then we check conflict with whole index, not a
> particular pages in it. Predicate lock on penging list pages will be
> effectively a lock over index, because every scan will begin from pending
> list and each insert will insert into it. I

Oh, right, that makes sense.  I'm not sure that the comments explain
this sufficiently -- I think it'd be good to expand that.


Given this patch, it seems clear that serializable mode is much worse
with fastupdate than without it!

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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