Re: Bug: Buffer cache is not scan resistant

Ühel kenal päeval, E, 2007-03-05 kell 03:51, kirjutas Luke Lonergan:
>  Hi Tom,
> 
> > Even granting that your conclusions are accurate, we are not 
> > in the business of optimizing Postgres for a single CPU architecture.
> 
> I think you're missing my/our point:
> 
> The Postgres shared buffer cache algorithm appears to have a bug.  When
> there is a sequential scan the blocks are filling the entire shared
> buffer cache.  This should be "fixed".
> 
> My proposal for a fix: ensure that when relations larger (much larger?)
> than buffer cache are scanned, they are mapped to a single page in the
> shared buffer cache.

How will this approach play together with synchronized scan patches ?

Or should synchronized scan rely on systems cache only ?

> - Luke
> 
> 
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