diff --git a/infra/specs/client.webrtc.json b/infra/specs/client.webrtc.json
index 15a55cc10f..36b67f74c3 100644
--- a/infra/specs/client.webrtc.json
+++ b/infra/specs/client.webrtc.json
@@ -10557,6 +10557,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -11535,6 +11536,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -12513,6 +12515,7 @@
           ],
           "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 f207c3da4f..6037ba6696 100644
--- a/infra/specs/test_suites.pyl
+++ b/infra/specs/test_suites.pyl
@@ -171,7 +171,7 @@
         'mixins': ['xcode_parallelization']
       },
       'svc_tests': {
-        'mixins': ['shards-4'],
+        'mixins': ['shards-4', 'cores-12'],
       },
       'system_wrappers_unittests': {},
       'test_support_unittests': {},
diff --git a/infra/specs/tryserver.webrtc.json b/infra/specs/tryserver.webrtc.json
index 666bbc7ec3..e7130369bc 100644
--- a/infra/specs/tryserver.webrtc.json
+++ b/infra/specs/tryserver.webrtc.json
@@ -3469,6 +3469,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -4447,6 +4448,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -5425,6 +5427,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }