e kernel's disk cache that will be used for
        <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
> data files.  Also, take
        into account the expected number of concurrent queries on different
        tables, since they will have to share the available
        space.  This parameter has no effect on the size of shared
        memory allocated by <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
>, nor
        does it reserve kernel disk cache; it is used only for estimation
        purposes.  The system also