diff --git a/infra/specs/client.webrtc.json b/infra/specs/client.webrtc.json
index d8469a317d..459d98f88a 100644
--- a/infra/specs/client.webrtc.json
+++ b/infra/specs/client.webrtc.json
@@ -10294,6 +10294,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -11273,6 +11274,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -12252,6 +12254,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
diff --git a/infra/specs/test_suites.pyl b/infra/specs/test_suites.pyl
index ece0551f69..1706f6d94d 100644
--- a/infra/specs/test_suites.pyl
+++ b/infra/specs/test_suites.pyl
@@ -190,7 +190,7 @@
         'mixins': ['shards-2'],
       },
       'modules_unittests': {
-        'mixins': ['shards-6'],
+        'mixins': ['shards-6', 'cores-12'],
       },
       'rtc_media_unittests': {},
       'rtc_pc_unittests': {},
diff --git a/infra/specs/tryserver.webrtc.json b/infra/specs/tryserver.webrtc.json
index 29d4fa1d63..5b84cc5762 100644
--- a/infra/specs/tryserver.webrtc.json
+++ b/infra/specs/tryserver.webrtc.json
@@ -2770,6 +2770,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -3749,6 +3750,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -4728,6 +4730,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }