diff --git a/distributed/worker.py b/distributed/worker.py
index 16a70db966..96cdf9e87e 100644
--- a/distributed/worker.py
+++ b/distributed/worker.py
@@ -557,7 +557,10 @@ def __init__(
                 deserialize_bytes,
                 File(path),
             )
-            target = int(float(self.memory_limit) * self.memory_target_fraction)
+            target = (
+                int(float(self.memory_limit) * self.memory_target_fraction)
+                or sys.maxsize
+            )
             self.data = Buffer({}, storage, target, weight)
             self.data.memory = self.data.fast
             self.data.disk = self.data.slow