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To: "Nikolas Everett" <nik9000@gmail.com>
Cc: "Greg Smith" <greg@2ndquadrant.com>, "Dave Crooke" <dcrooke@gmail.com>,
	"Paul McGarry" <paul@paulmcgarry.com>, pgsql-performance@postgresql.org
Subject: Re: shared_buffers advice
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> I think the logic you are referring to is the clock sweep buffer  
> accounting
> scheme.  That just makes sure that the most popular pages stay in the
> buffers.  If your entire db fits in the buffer pool then it'll all get in
> there real fast.


Actually, I meant that in the case of a seq scan, PG will try to use just  
a few buffers (a ring) in shared_buffers instead of thrashing the whole  
buffers. But if there was actually a lot of free space in shared_buffers,  
do the pages stay, or do they not ?