diff --git a/lib/dns/tests/Kyuafile b/lib/dns/tests/Kyuafile
index 692acc0500..221fb54ffe 100644
--- a/lib/dns/tests/Kyuafile
+++ b/lib/dns/tests/Kyuafile
@@ -18,7 +18,7 @@ atf_test_program{name='name_test'}
 atf_test_program{name='nsec3_test'}
 atf_test_program{name='peer_test'}
 atf_test_program{name='private_test'}
-atf_test_program{name='rbt_serialize_test'}
+atf_test_program{name='rbt_serialize_test', is_exclusive=true}
 atf_test_program{name='rbt_test'}
 atf_test_program{name='rdata_test'}
 atf_test_program{name='rdataset_test'}
diff --git a/unit/unittest.sh.in b/unit/unittest.sh.in
index bcbb89394e..70335aa7b3 100755
--- a/unit/unittest.sh.in
+++ b/unit/unittest.sh.in
@@ -30,7 +30,7 @@ then
 	echo "S:unit:`date`"
 	echo "T:unit:1:A"
 	echo "I: unit tests (using kyua)"
-	kyua --logfile kyua.log --loglevel debug test --results-file ${KYUA_RESULT:-NEW}
+	kyua -v parallelism=${TEST_PARALLEL_JOBS:-1} --logfile kyua.log --loglevel debug test --results-file ${KYUA_RESULT:-NEW}
 	status=$?
 
 	kyua report --results-file ${KYUA_RESULT:-LATEST}