diff --git a/synapse/tests/test_cortex.py b/synapse/tests/test_cortex.py
index 3c9fd778f3..692d007bd3 100644
--- a/synapse/tests/test_cortex.py
+++ b/synapse/tests/test_cortex.py
@@ -4857,7 +4857,7 @@ async def test_cortex_view_persistence(self):
         with self.getTestDir() as dirn:
             async with self.getTestCore(dirn=dirn) as core:
                 view = core.view
-                NKIDS = 20
+                NKIDS = 3
                 for _ in range(NKIDS):
                     await view.fork()