Index: lldb/trunk/test/functionalities/thread/concurrent_events/TestConcurrentEvents.py
===================================================================
--- lldb/trunk/test/functionalities/thread/concurrent_events/TestConcurrentEvents.py
+++ lldb/trunk/test/functionalities/thread/concurrent_events/TestConcurrentEvents.py
@@ -70,6 +70,7 @@
         self.do_thread_actions(num_breakpoint_threads=1, num_signal_threads=1)
 
     @dwarf_test
+    @expectedFailureLinux # this test fails 2/100 dosep runs
     def test_delay_signal_break_dwarf(self):
         """Test (1-second delay) signal and a breakpoint in multiple threads."""
         self.buildDwarf(dictionary=self.getBuildFlags())
Index: lldb/trunk/test/functionalities/thread/create_after_attach/TestCreateAfterAttach.py
===================================================================
--- lldb/trunk/test/functionalities/thread/create_after_attach/TestCreateAfterAttach.py
+++ lldb/trunk/test/functionalities/thread/create_after_attach/TestCreateAfterAttach.py
@@ -32,6 +32,7 @@
     @skipIfFreeBSD # Hangs. Revisit once required functionality is implemented
                    # for FreeBSD.
     @dwarf_test
+    @expectedFailureLinux # this test fails 1/100 dosep runs
     def test_create_after_attach_with_dwarf_and_fork(self):
         """Test thread creation after process attach."""
         self.buildDwarf(dictionary=self.getBuildFlags(use_cpp11=False))
Index: lldb/trunk/test/functionalities/thread/thread_specific_break/TestThreadSpecificBreakpoint.py
===================================================================
--- lldb/trunk/test/functionalities/thread/thread_specific_break/TestThreadSpecificBreakpoint.py
+++ lldb/trunk/test/functionalities/thread/thread_specific_break/TestThreadSpecificBreakpoint.py
@@ -23,6 +23,7 @@
     @expectedFailureFreeBSD('llvm.org/pr18522') # hits break in another thread in testrun
     @python_api_test
     @dwarf_test
+    @expectedFailureLinux # this test fails 6/100 dosep runs
     def test_with_dwarf_python(self):
         """Test that we obey thread conditioned breakpoints."""
         self.buildDwarf()
Index: lldb/trunk/test/python_api/process/io/TestProcessIO.py
===================================================================
--- lldb/trunk/test/python_api/process/io/TestProcessIO.py
+++ lldb/trunk/test/python_api/process/io/TestProcessIO.py
@@ -21,6 +21,7 @@
     @unittest2.skipIf(sys.platform.startswith("win32"), "stdio manipulation unsupported on Windows")
     @python_api_test
     @dwarf_test
+    @expectedFailureLinux # this test fails 7/100 dosep runs
     def test_stdin_by_api_with_dwarf(self):
         """Exercise SBProcess.PutSTDIN()."""
         self.buildDwarf()
@@ -37,6 +38,7 @@
     @unittest2.skipIf(sys.platform.startswith("win32"), "stdio manipulation unsupported on Windows")
     @python_api_test
     @dwarf_test
+    @expectedFailureLinux # this test fails 4/100 dosep runs
     def test_stdin_redirection_with_dwarf(self):
         """Exercise SBLaunchInfo::AddOpenFileAction() for STDIN without specifying STDOUT or STDERR."""
         self.buildDwarf()
@@ -53,6 +55,7 @@
     @unittest2.skipIf(sys.platform.startswith("win32"), "stdio manipulation unsupported on Windows")
     @python_api_test
     @dwarf_test
+    @expectedFailureLinux # this test fails 2/100 dosep runs
     def test_stdout_redirection_with_dwarf(self):
         """Exercise SBLaunchInfo::AddOpenFileAction() for STDOUT without specifying STDIN or STDERR."""
         self.buildDwarf()
@@ -69,6 +72,7 @@
     @unittest2.skipIf(sys.platform.startswith("win32"), "stdio manipulation unsupported on Windows")
     @python_api_test
     @dwarf_test
+    @expectedFailureLinux # this test fails 5/100 dosep runs
     def test_stderr_redirection_with_dwarf(self):
         """Exercise SBLaunchInfo::AddOpenFileAction() for STDERR without specifying STDIN or STDOUT."""
         self.buildDwarf()
Index: lldb/trunk/test/python_api/signals/TestSignalsAPI.py
===================================================================
--- lldb/trunk/test/python_api/signals/TestSignalsAPI.py
+++ lldb/trunk/test/python_api/signals/TestSignalsAPI.py
@@ -12,6 +12,7 @@
     mydir = TestBase.compute_mydir(__file__)
 
     @python_api_test
+    @expectedFailureLinux # this test fails 1/100 dosep runs
     def test_ignore_signal(self):
         """Test Python SBUnixSignals.Suppress/Stop/Notify() API."""
         self.buildDefault()
Index: lldb/trunk/test/python_api/value/change_values/TestChangeValueAPI.py
===================================================================
--- lldb/trunk/test/python_api/value/change_values/TestChangeValueAPI.py
+++ lldb/trunk/test/python_api/value/change_values/TestChangeValueAPI.py
@@ -24,6 +24,7 @@
 
     @python_api_test
     @dwarf_test
+    @expectedFailureLinux # this test fails 6/100 dosep runs
     def test_change_value_with_dwarf(self):
         """Exercise the SBValue::SetValueFromCString API."""
         d = {'EXE': self.exe_name}
Index: lldb/trunk/test/python_api/watchpoint/watchlocation/TestSetWatchlocation.py
===================================================================
--- lldb/trunk/test/python_api/watchpoint/watchlocation/TestSetWatchlocation.py
+++ lldb/trunk/test/python_api/watchpoint/watchlocation/TestSetWatchlocation.py
@@ -32,6 +32,7 @@
 
     @python_api_test
     @dwarf_test
+    @expectedFailureLinux # fails in 10/100 dosep runs
     def test_watch_location_with_dwarf(self):
         """Exercise SBValue.WatchPointee() API to set a watchpoint."""
         self.buildDwarf()
Index: lldb/trunk/test/python_api/watchpoint/watchlocation/TestTargetWatchAddress.py
===================================================================
--- lldb/trunk/test/python_api/watchpoint/watchlocation/TestTargetWatchAddress.py
+++ lldb/trunk/test/python_api/watchpoint/watchlocation/TestTargetWatchAddress.py
@@ -32,6 +32,7 @@
 
     @python_api_test
     @dwarf_test
+    @expectedFailureLinux # failed 11/100 dosep runs
     def test_watch_address_with_dwarf(self):
         """Exercise SBTarget.WatchAddress() API to set a watchpoint."""
         self.buildDwarf()