diff --git a/tezt/tests/demo_protocols.ml b/tezt/tests/demo_protocols.ml
index 50fc7fe00988534da9bc5a97e43fc7eaad2888a0..c578dfa9672ae02f5ada4901d544fc1bd0ec79d5 100644
--- a/tezt/tests/demo_protocols.ml
+++ b/tezt/tests/demo_protocols.ml
@@ -93,7 +93,10 @@ module Demo_counter = struct
     unit
 
   let register () =
-    Test.register ~__FILE__ ~title:"demo_counter" ~tags:["demo_counter"]
+    Test.register
+      ~__FILE__
+      ~title:"demo_counter"
+      ~tags:["demo_counter"; (* Uses about 1.1GB of memory. *) Tag.memory_3k]
     @@ fun () ->
     let* node = Node.init [Synchronisation_threshold 0] in
     let* client = Client.init ~endpoint:(Node node) () in
@@ -155,7 +158,10 @@ module Demo_noops = struct
           (JSON.encode_u protocol_data)
 
   let register () =
-    Test.register ~__FILE__ ~title:"demo_noops" ~tags:["demo_noops"]
+    Test.register
+      ~__FILE__
+      ~title:"demo_noops"
+      ~tags:["demo_noops"; (* Uses about 1.1GB of memory. *) Tag.memory_3k]
     @@ fun () ->
     let* node = Node.init [Synchronisation_threshold 0] in
     let* client = Client.init ~endpoint:(Node node) () in
diff --git a/tezt/tests/p2p.ml b/tezt/tests/p2p.ml
index 1d8210dc74d37a957190e47d4c7f58aacda569bd..90755bd7e6c1451d901e9483725a3de1cd6d79c1 100644
--- a/tezt/tests/p2p.ml
+++ b/tezt/tests/p2p.ml
@@ -209,7 +209,15 @@ module Maintenance = struct
     Test.register
       ~__FILE__
       ~title:"p2p-maintenance-disabled"
-      ~tags:[team; "p2p"; "node"; "maintenance"]
+      ~tags:
+        [
+          team;
+          "p2p";
+          "node";
+          "maintenance";
+          (* Uses about 1.7GB of memory. *)
+          Tag.memory_3k;
+        ]
       ~uses_client:false
       ~uses_admin_client:false
     @@ fun () ->
@@ -325,7 +333,15 @@ module Maintenance = struct
     Test.register
       ~__FILE__
       ~title:"p2p-maintenance-init-expected_connections"
-      ~tags:[team; "p2p"; "node"; "maintenance"; Tag.memory_4k]
+      ~tags:
+        [
+          team;
+          "p2p";
+          "node";
+          "maintenance";
+          (* Uses about 4.8GB of memory. *)
+          Tag.memory_4k;
+        ]
     @@ fun () ->
     (* Connections values evaluated from --connections option. *)
     let min_connections = expected_connections / 2 in
@@ -591,7 +607,15 @@ module Swap = struct
     Test.register
       ~__FILE__
       ~title:"p2p-swap-disable"
-      ~tags:[team; "p2p"; "node"; "swap"; Tag.memory_4k]
+      ~tags:
+        [
+          team;
+          "p2p";
+          "node";
+          "swap";
+          (* Uses about 3.4GB of memory. *)
+          Tag.memory_4k;
+        ]
       ~uses_client:false
       ~uses_admin_client:false
     @@ fun () ->
@@ -1400,7 +1424,15 @@ module Peer_discovery = struct
     Test.register
       ~__FILE__
       ~title:"p2p-peer-discovery"
-      ~tags:[team; "p2p"; "node"; "peer_discovery"]
+      ~tags:
+        [
+          team;
+          "p2p";
+          "node";
+          "peer_discovery";
+          (* Uses about 1.7GB of memory. *)
+          Tag.memory_3k;
+        ]
       ~uses_client:false
       ~uses_admin_client:false
     @@ fun () ->
@@ -1417,7 +1449,15 @@ module Peer_discovery = struct
     Test.register
       ~__FILE__
       ~title:"p2p-peer-discovery-disable"
-      ~tags:[team; "p2p"; "node"; "peer_discovery"]
+      ~tags:
+        [
+          team;
+          "p2p";
+          "node";
+          "peer_discovery";
+          (* Uses about 1.7GB of memory. *)
+          Tag.memory_3k;
+        ]
       ~uses_client:false
       ~uses_admin_client:false
     @@ fun () ->