+See L<public-inbox-index(1)/--no-fsync> for caveats.
+
+Available in public-inbox 1.6.0+.
+
+=item --sequential-shard
+
+Copy each shard sequentially, ignoring C<--jobs>. This also
+affects indexing done at the end of a run.
+
+=item --batch-size=BYTES
+
+=item --max-size=BYTES
+
+See L<public-inbox-index(1)> for a description of these options.