8323640: [TESTBUG]testMemoryFailCount in jdk/internal/platform/docker/TestDockerMemoryMetrics.java always fail because OOM killed

Reviewed-by: phh
Backport-of: 791b427f4410057cdcdf8fd8ea0dcce71f7dc513

Author: SendaoYan

jdk/test/jdk/internal/platform/docker/MetricsMemoryTester.java

@@ -75,12 +75,12 @@ private static void testMemoryFailCount() {
         } else {
             long count = Metrics.systemMetrics().getMemoryFailCount();
 
-            // Allocate 512M of data
-            byte[][] bytes = new byte[64][];
+            // Allocate 512M of data in 1M chunks per iteration
+            byte[][] bytes = new byte[64 * 8][];
             boolean atLeastOneAllocationWorked = false;
-            for (int i = 0; i < 64; i++) {
+            for (int i = 0; i < 64 * 8; i++) {
                 try {
-                    bytes[i] = new byte[8 * 1024 * 1024];
+                    bytes[i] = new byte[1024 * 1024];
                     atLeastOneAllocationWorked = true;
                     // Break out as soon as we see an increase in failcount
                     // to avoid getting killed by the OOM killer.