> > I tried to implement LRU-2 awhile ago, and got discouraged when I
> > couldn't see any performance improvement. But I was using pgbench as
> > the test case, and failed to think about its lack of seqscans.
> Yes , lru-2 will behave like LRU under 'normal' load. it will detect
> sequential scans and adapt to it. I think that was why you didn't
> see any substantial gain in cache hits. though I think ARC does a better
> job. LRU-2 also has logaritmic complexity overhead.
> The ARC guys have tested with real traces from a Db of a large insurrance
> company and the results were quite encouraging. (a lot of other traces
> where examined as well)
> > We could probably resurrect that code for comparison to 2Q, if anyone
> > can devise more interesting benchmark cases to test.
> As i stated before, i'm willing to implement ARC and to see how they all
Bruce Momjian | http://candle.pha.pa.us
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