diff --git a/install/setup_cassandra.sh b/install/setup_cassandra.sh
index 463d7f1d2..57a9a81e2 100755
--- a/install/setup_cassandra.sh
+++ b/install/setup_cassandra.sh
@@ -24,6 +24,11 @@
 ###############################################################################
 # Configure Cassandra
 ###############################################################################
+
+# update the per-thread stack size. this used to be set to 256k in cassandra
+# version 1.2.19, but we recently downgraded to 1.2.11 where it's set too low
+sed -i -e 's/-Xss180k/-Xss256k/g' /etc/cassandra/cassandra-env.sh
+
 python <<END
 import pycassa
 sys = pycassa.SystemManager("localhost:9160")