Re: limiting hint bit I/O

On Fri, Jan 14, 2011 at 1:42 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> "Kevin Grittner" <Kevin.Grittner@wicourts.gov> writes:
>> Anyway, there are so many ideas in this area, it's hard to keep them
>> all straight.  Personally, if I was going to start with something,
>> it would probably be to better establish what the impact is on
>> various workloads of *eliminating* hint bits.
>
>> I know some people find them useful for forensics to a degree that
>> they would prefer not to see this,
>
> Um, yeah, I think you're having a problem keeping all the ideas straight
> ;-).  The argument about forensics has to do with how soon we're willing
> to freeze tuples, ie replace the XID with a constant.  Not about hint
> bits.

Those things are related, though.  Freezing sooner could be viewed as
an alternative to hint bits.  Trouble is, it breaks Hot Standby,
badly.

--
Robert Haas
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