these
        operations can be executed at a time by a database session, and
        an installation normally doesn't have many of them running
        concurrently, it's safe to set this value significantly larger
        than <code class="varname">work_mem</code>.  Larger settings might improve
        performance for vacuuming and for restoring database dumps.
       </p><p>
        Note that when autovacuum runs, up to
        <a class="xref" href="runtime-config-autovacuum.html#GUC-AUTOVACUUM-MAX-WORK