Re: effective_cache_size less than shared_buffers

Greg,

>
> Well we won't eliminate any problems unless we actually override the
> effective_cache_size setting by clipping it to shared_buffers. I don't
> really see much of a problem doing that. The only case where that
> would annoy someone was if they're intentionally understating
> effective_cache_size to push the planner into avoiding nested loops
> and I doin't think it's a powerful enough knob to be very likely used
> that way.
>

My experience from PostgreSQL on Windows: effective_cache_size should
reflect the value of "system cache" from task manager. shared_buffers (on
windows) should be rather small.

My real-workload-tests (no benchmarks, real usage of DB-Server) showed that
big shared buffers on Windows have a negative effect on PostgreSQL
performance. I have found no explanation WHY it is this way.

Harald

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GHUM Harald Massa
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