diff --git a/tests/unit/util/test_prometheus_exporter.py b/tests/unit/util/test_prometheus_exporter.py
index 6a88b8ddc..5fdf30ba7 100644
--- a/tests/unit/util/test_prometheus_exporter.py
+++ b/tests/unit/util/test_prometheus_exporter.py
@@ -13,8 +13,12 @@
 from logprep.util.prometheus_exporter import PrometheusStatsExporter
 
 
+@mock.patch(
+    "logprep.util.prometheus_exporter.PrometheusStatsExporter._prepare_multiprocessing",
+    new=lambda *args, **kwargs: None,
+)
 class TestPrometheusStatsExporter:
-    def setup_method(self):
+    def setup_method(self, tmpdir):
         REGISTRY.__init__()
         self.metrics_config = {
             "metrics": {"period": 10, "enabled": True, "cumulative": True, "port": 80}
@@ -40,53 +44,6 @@ def test_default_port_if_missing_in_config(self):
 
         assert exporter._port == 8000
 
-    @mock.patch("logprep.util.prometheus_exporter.multiprocess")
-    def test_prepare_multiprocessing_recreates_temp_directory_if_dir_exists_already(
-        self, mock_multiprocess, tmp_path
-    ):
-        multi_proc_dir = tmp_path / "multi_proc_dir"
-        os.makedirs(multi_proc_dir)
-        test_file = os.path.join(multi_proc_dir, "dummy.txt")
-        open(test_file, "w", encoding="utf-8").close()  # pylint: disable=consider-using-with
-
-        with mock.patch.dict(os.environ, {"PROMETHEUS_MULTIPROC_DIR": str(multi_proc_dir)}):
-            _ = PrometheusStatsExporter(self.metrics_config, getLogger("test-logger"))
-
-        assert os.path.isdir(multi_proc_dir)
-        assert not os.path.isfile(test_file)
-        mock_multiprocess.assert_has_calls(
-            [mock.call.MultiProcessCollector(REGISTRY, str(multi_proc_dir))]
-        )
-
-    @mock.patch("logprep.util.prometheus_exporter.multiprocess")
-    def test_prepare_multiprocessing_creates_temp_dir_if_dir_does_not_exists(
-        self, mock_multiprocess, tmp_path
-    ):
-        multi_proc_dir = tmp_path / "multi_proc_dir"
-        assert not os.path.isdir(multi_proc_dir)
-
-        with mock.patch.dict(os.environ, {"PROMETHEUS_MULTIPROC_DIR": str(multi_proc_dir)}):
-            _ = PrometheusStatsExporter(self.metrics_config, getLogger("test-logger"))
-
-        assert os.path.isdir(multi_proc_dir)
-        mock_multiprocess.assert_has_calls(
-            [mock.call.MultiProcessCollector(REGISTRY, str(multi_proc_dir))]
-        )
-
-    def test_prepare_multiprocessing_fails_if_env_variable_is_file(self, tmp_path):
-        multi_proc_dir = tmp_path / "multi_proc_dir"
-        os.makedirs(multi_proc_dir)
-        test_file = os.path.join(multi_proc_dir, "dummy.txt")
-        open(test_file, "w", encoding="utf-8").close()  # pylint: disable=consider-using-with
-
-        with mock.patch.dict(os.environ, {"PROMETHEUS_MULTIPROC_DIR": str(test_file)}):
-            with pytest.raises(
-                ValueError,
-                match="Environment variable 'PROMETHEUS_MULTIPROC_DIR' "
-                "is a file and not a directory",
-            ):
-                _ = PrometheusStatsExporter(self.metrics_config, getLogger("test-logger"))
-
     @mock.patch("logprep.util.prometheus_exporter.start_http_server")
     def test_run_starts_http_server(self, mock_http_server, caplog):
         with caplog.at_level(logging.INFO):
@@ -95,23 +52,3 @@ def test_run_starts_http_server(self, mock_http_server, caplog):
 
         mock_http_server.assert_has_calls([mock.call(exporter._port)])
         assert f"Prometheus Exporter started on port {exporter._port}" in caplog.text
-
-    def test_remove_metrics_from_process_removes_database_file_of_given_pid(self, tmp_path, caplog):
-        # pylint: disable=consider-using-with
-        multi_proc_dir = tmp_path / "multi_proc_dir"
-        os.makedirs(multi_proc_dir)
-
-        with mock.patch.dict(os.environ, {"PROMETHEUS_MULTIPROC_DIR": str(multi_proc_dir)}):
-            with caplog.at_level(logging.DEBUG):
-                exporter = PrometheusStatsExporter(self.metrics_config, getLogger("test-logger"))
-                metric_file_5416 = multi_proc_dir / "gauge_5416.db"
-                metric_file_8742 = multi_proc_dir / "gauge_8742.db"
-                open(metric_file_5416, "a", encoding="utf-8").close()
-                open(metric_file_8742, "a", encoding="utf-8").close()
-
-                exporter.remove_metrics_from_process(pid=5416)
-
-            assert not os.path.exists(metric_file_5416)
-            assert os.path.exists(metric_file_8742)
-            assert os.path.isfile(metric_file_8742)
-            assert "Removed stale metric files: ['gauge_5416.db']" in caplog.text