ased vacuuming.
        </p><p>
         When using cost-based vacuuming, appropriate values for
         <code class="varname">vacuum_cost_delay</code> are usually quite small, perhaps
         less than 1 millisecond.  While <code class="varname">vacuum_cost_delay</code>
         can be set to fractional-millisecond values, such delays may not be
         measured accurately on older platforms.  On such platforms,
         increasing <code class="command">VACUUM</code>'s throttled resource consumption
   