2 files changed, 8 insertions, 2 deletions
diff --git a/test/-ext-/thread/test_instrumentation_api.rb b/test/-ext-/thread/test_instrumentation_api.rb
index 663e41be53..ba41069304 100644
--- a/test/-ext-/thread/test_instrumentation_api.rb
+++ b/test/-ext-/thread/test_instrumentation_api.rb
@@ -151,7 +151,7 @@ class TestThreadInstrumentation < Test::Unit::TestCase
       end
 
       full_timeline = record do
-        ractor.take
+        ractor.value
       end
 
       timeline = timeline_for(Thread.current, full_timeline)
@@ -161,6 +161,8 @@ class TestThreadInstrumentation < Test::Unit::TestCase
   end
 
   def test_sleeping_inside_ractor
+    omit "This test is flaky and intermittently failing now on ModGC workflow" if ENV['GITHUB_WORKFLOW'] == 'ModGC'
+
     assert_ractor(<<-"RUBY", require_relative: "helper", require: "-test-/thread/instrumentation")
       include ThreadInstrumentation::TestHelper
 
@@ -170,7 +172,7 @@ class TestThreadInstrumentation < Test::Unit::TestCase
         thread = Ractor.new{
           sleep 0.1
           Thread.current
-        }.take
+        }.value
         sleep 0.1
       end
 
diff --git a/test/-ext-/thread/test_lock_native_thread.rb b/test/-ext-/thread/test_lock_native_thread.rb
index 8a5ba78838..b4044b2b93 100644
--- a/test/-ext-/thread/test_lock_native_thread.rb
+++ b/test/-ext-/thread/test_lock_native_thread.rb
@@ -15,6 +15,8 @@ end
 
 class TestThreadLockNativeThread < Test::Unit::TestCase
   def test_lock_native_thread
+    omit "LSAN reports memory leak because NT is not freed for MN thread" if Test::Sanitizers.lsan_enabled?
+
     assert_separately([{'RUBY_MN_THREADS' => '1'}], <<-RUBY)
       require '-test-/thread/lock_native_thread'
 
@@ -28,6 +30,8 @@ class TestThreadLockNativeThread < Test::Unit::TestCase
   end
 
   def test_lock_native_thread_tls
+    omit "LSAN reports memory leak because NT is not freed for MN thread" if Test::Sanitizers.lsan_enabled?
+
     assert_separately([{'RUBY_MN_THREADS' => '1'}], <<-RUBY)
       require '-test-/thread/lock_native_thread'
       tn = 10