diff --git a/.github/workflows/python-package.yml b/.github/workflows/python-package.yml
index 81ed0c6..7a8afa6 100644
--- a/.github/workflows/python-package.yml
+++ b/.github/workflows/python-package.yml
@@ -16,8 +16,12 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
-        python-version: ['3.6', '3.7', '3.8', '3.9']
-
+        python-version: ['3.7', '3.8', '3.9']
+        include:
+          - os: macos-latest
+            python-version: '3.6'
+          - os: windows-latest
+            python-version: '3.6'
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python ${{ matrix.python-version }}
diff --git a/codeguru_profiler_agent/codeguru_client_builder.py b/codeguru_profiler_agent/codeguru_client_builder.py
index bb9b767..876b565 100644
--- a/codeguru_profiler_agent/codeguru_client_builder.py
+++ b/codeguru_profiler_agent/codeguru_client_builder.py
@@ -42,8 +42,11 @@ def _create_codeguru_client(self):
         region = self._get_region_or_default()
 
         # the default retry mode is 'legacy', not 'standard'
+        # retry at most once to avoid retry storms
+        # see https://boto3.amazonaws.com/v1/documentation/api/latest/guide/retries.html
         standard_config = Config(
-            retries={
+            retries = {
+                'max_attempts': 1,
                 'mode': 'standard'
             }
         )
diff --git a/release_layer.py b/release_layer.py
index 0d1f336..a7da27c 100755
--- a/release_layer.py
+++ b/release_layer.py
@@ -8,7 +8,7 @@
 
 # The following values are used in the documentation, so any change of them requires updates to the documentation.
 LAYER_NAME = 'AWSCodeGuruProfilerPythonAgentLambdaLayer'
-SUPPORTED_VERSIONS = ['3.6', '3.7', '3.8', '3.9']
+SUPPORTED_VERSIONS = ['3.7', '3.8', '3.9']
 EXEC_SCRIPT_FILE_NAME = 'codeguru_profiler_lambda_exec'
 
 # We should release in all the regions that lambda layer is supported, not just the ones CodeGuru Profiler Service supports.
diff --git a/test/unit/metrics/test_with_timer.py b/test/unit/metrics/test_with_timer.py
index 29c830e..b25303a 100644
--- a/test/unit/metrics/test_with_timer.py
+++ b/test/unit/metrics/test_with_timer.py
@@ -15,7 +15,9 @@ def foo_wall(self):
     @with_timer(metric_name="test-foo-cpu", measurement="cpu-time")
     def foo_cpu(self):
         # Run something to make sure the cpu clock does tick (https://bugs.python.org/issue37859)
-        len(str(2 ** 500_000))
+        sum_x = 0
+        for i in range(10000000):
+            sum_x += i
         return