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Old 04-18-2008, 10:39 AM
Tom Lane
 
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Default Re: [HACKERS] Aggressive freezing in lazy-vacuum

ITAGAKI Takahiro <itagaki.takahiro@oss.ntt.co.jp> writes:
> This is a stand-alone patch for aggressive freezing. I'll propose
> to use OldestXmin instead of FreezeLimit as the freeze threshold
> in the circumstances below:


I think it's a really bad idea to freeze that aggressively under any
circumstances except being told to (ie, VACUUM FREEZE). When you
freeze, you lose history information that might be needed later --- for
forensic purposes if nothing else. You need to show a fairly amazing
performance gain to justify that, and I don't think you can.

regards, tom lane

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