Re: init_sequence spill to hash table

On 2013-11-14 09:47:18 -0500, Tom Lane wrote:
> Andres Freund <andres@2ndquadrant.com> writes:
> > On 2013-11-14 09:23:20 -0500, Tom Lane wrote:
> >> We most certainly *do* discard entries, if they're not open when a cache
> >> flush event comes along.
> 
> > What I was aiming at is that we don't discard them because of a limited
> > cache size. I don't think it means much that we flush the entry when
> > it's changed but not referenced.
> 
> Well, I don't want non-user-significant events (such as an sinval queue
> overrun) causing sequence state to get discarded.  We would get bug
> reports about lost sequence values.

But we can easily do as you suggest and simply retain the entry in that
case. I am just not seeing the memory overhead argument as counting much
since we don't protect against it in normal operation.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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