Re: Protect syscache from bloating with negative cache entries

On 2019-Feb-15, Tomas Vondra wrote:

> ISTM there's a couple of ways to deal with that:
> 
> 1) Ignore the memory amounts entirely, and do just time-base eviction.
> 
> 2) If we want some size thresholds (e.g. to disable eviction for
> backends with small caches etc.) use the number of entries instead. I
> don't think that's particularly worse that specifying size in MB.

Why is there a *need* for size-based eviction?  Seems that time-based
should be sufficient.  Is the proposed approach to avoid eviction at all
until the size threshold has been reached?  I'm not sure I see the point
of that.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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