diff --git a/config/clusters/utoronto/common.values.yaml b/config/clusters/utoronto/common.values.yaml
index 7eed5f9b7..bb922ea47 100644
--- a/config/clusters/utoronto/common.values.yaml
+++ b/config/clusters/utoronto/common.values.yaml
@@ -47,6 +47,13 @@ jupyterhub:
               ongoing basis. To reach the support site, please visit: <a href="https://act.utoronto.ca/jupyterhub-support">https://act.utoronto.ca/jupyterhub-support/</a>.
             </div>
   singleuser:
+    cpu:
+      # Each node has about 8 CPUs total, and if we limit users to no more than
+      # 4, no single user can take down a full node by themselves. We have to
+      # set the guarantee to *something*, otherwise it is set to be equal
+      # to the limit!
+      limit: 4
+      guarantee: 0.01
     memory:
       limit: 2G
       guarantee: 1G