--- old/test/TestCommon.gmk	2018-01-31 16:28:28.000000000 -0800
+++ new/test/TestCommon.gmk	2018-01-31 16:28:27.000000000 -0800
@@ -358,7 +358,7 @@
 endif
 
 # Concurrency based on min(cores / 2, 12) * CONCURRENCY_FACTOR
-CONCURRENCY := $(shell awk \
+CONCURRENCY := $(shell $(AWK) \
   'BEGIN { \
     c = $(NUM_CORES) / 2; \
     if (c > 12) c = 12; \
@@ -368,8 +368,10 @@
   }')
 JTREG_BASIC_OPTIONS += -concurrency:$(CONCURRENCY)
 
-# Make sure MaxRAMPercentage is high enough to not cause OOM or swapping since we may end up with a lot of JVM's
-JTREG_BASIC_OPTIONS += -vmoption:-XX:MaxRAMPercentage=$(shell expr 25 / $(CONCURRENCY))
+# Make sure MaxRAMPercentage is low enough to not cause OOM or swapping since
+# we may end up with a lot of JVM's
+MAX_RAM_PERCENTAGE := $(shell expr 25 / $(CONCURRENCY))
+JTREG_BASIC_OPTIONS += -vmoption:-XX:MaxRAMPercentage=$(MAX_RAM_PERCENTAGE)
 
 ifdef EXTRA_JTREG_OPTIONS
   JTREG_BASIC_OPTIONS += $(EXTRA_JTREG_OPTIONS)