diff --git a/util/cron/test-perf.hpe-cray-ex.ofi.bash b/util/cron/test-perf.hpe-cray-ex.ofi.bash
index c541971c5f0..5d8b8e496fe 100755
--- a/util/cron/test-perf.hpe-cray-ex.ofi.bash
+++ b/util/cron/test-perf.hpe-cray-ex.ofi.bash
@@ -16,7 +16,7 @@ source $CWD/common-ofi.bash || \
 source $CWD/common-hpe-cray-ex.bash
 
 export CHPL_RT_COMM_OFI_EXPECTED_PROVIDER="cxi"
-export CHPL_RT_MAX_HEAP_SIZE=16g
+export CHPL_RT_MAX_HEAP_SIZE="50%"
 
 nightly_args="${nightly_args} -no-buildcheck"
 perf_args="-performance -perflabel ml- -numtrials 1"