7.7.2.2.1.3" class="indexterm"></a>
       </span> <a href="#GUC-EFFECTIVE-IO-CONCURRENCY" class="id_link">#</a></dt><dd><p>
         Sets the number of concurrent disk I/O operations that
         <span class="productname">PostgreSQL</span> expects can be executed
         simultaneously.  Raising this value will increase the number of I/O
         operations that any individual <span class="productname">PostgreSQL</span> session
         attempts to initiate in parallel.  The allowed range is 1 to 1000,
 