--- a/test/lib/jdk/test/lib/containers/cgroup/MetricsTester.java	Thu Oct 17 20:27:44 2019 +0100
+++ b/test/lib/jdk/test/lib/containers/cgroup/MetricsTester.java	Thu Oct 17 20:53:35 2019 +0100
@@ -26,6 +26,7 @@
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.math.BigInteger;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -157,7 +158,24 @@
 
     private static long getLongValueFromFile(SubSystem subSystem, String fileName) {
         String data = getFileContents(subSystem, fileName);
-        return data.isEmpty() ? 0L : Long.parseLong(data);
+        return data.isEmpty() ? 0L : convertStringToLong(data);
+    }
+
+    private static long convertStringToLong(String strval) {
+        long retval = 0;
+        if (strval == null) return 0L;
+
+        try {
+            retval = Long.parseLong(strval);
+        } catch (NumberFormatException e) {
+            // For some properties (e.g. memory.limit_in_bytes) we may overflow the range of signed long.
+            // In this case, return Long.MAX_VALUE
+            BigInteger b = new BigInteger(strval);
+            if (b.compareTo(BigInteger.valueOf(Long.MAX_VALUE)) > 0) {
+                return Long.MAX_VALUE;
+            }
+        }
+        return retval;
     }
 
     private static long getLongValueFromFile(SubSystem subSystem, String metric, String subMetric) {
@@ -165,7 +183,8 @@
         String[] tokens = stats.split("[\\r\\n]+");
         for (int i = 0; i < tokens.length; i++) {
             if (tokens[i].startsWith(subMetric)) {
-                return Long.parseLong(tokens[i].split("\\s+")[1]);
+                String strval = tokens[i].split("\\s+")[1];
+                return convertStringToLong(strval);
             }
         }
         return 0L;
@@ -531,16 +550,20 @@
         long newUsage = metrics.getCpuUsage();
         long[] newPerCpu = metrics.getPerCpuUsage();
 
-        if (newSysVal <= startSysVal) {
+        // system/user CPU usage counters may be slowly increasing.
+        // allow for equal values for a pass
+        if (newSysVal < startSysVal) {
             fail(SubSystem.CPU, "getCpuSystemUsage", newSysVal, startSysVal);
         }
 
-        if (newUserVal <= startUserVal) {
+        // system/user CPU usage counters may be slowly increasing.
+        // allow for equal values for a pass
+        if (newUserVal < startUserVal) {
             fail(SubSystem.CPU, "getCpuUserUsage", newUserVal, startUserVal);
         }
 
         if (newUsage <= startUsage) {
-            fail(SubSystem.CPU, "getCpuUserUsage", newUsage, startUsage);
+            fail(SubSystem.CPU, "getCpuUsage", newUsage, startUsage);
         }
 
         boolean success = false;
@@ -559,19 +582,28 @@
         Metrics metrics = Metrics.systemMetrics();
         long memoryMaxUsage = metrics.getMemoryMaxUsage();
         long memoryUsage = metrics.getMemoryUsage();
-
-        long[] ll = new long[64*1024*1024]; // 64M
+        long newMemoryMaxUsage = 0, newMemoryUsage = 0;
 
-        long newMemoryMaxUsage = metrics.getMemoryMaxUsage();
-        long newMemoryUsage = metrics.getMemoryUsage();
+        // allocate memory in a loop and check more than once for new values
+        // otherwise we might see seldom the effect of decreasing new memory values
+        // e.g. because the system could free up memory
+        byte[][] bytes = new byte[32][];
+        for (int i = 0; i < 32; i++) {
+            bytes[i] = new byte[8*1024*1024];
+            newMemoryUsage = metrics.getMemoryUsage();
+            if (newMemoryUsage > memoryUsage) {
+                break;
+            }
+        }
+        newMemoryMaxUsage = metrics.getMemoryMaxUsage();
 
-        if(newMemoryMaxUsage < memoryMaxUsage) {
-            fail(SubSystem.MEMORY, "getMemoryMaxUsage", newMemoryMaxUsage,
-                    memoryMaxUsage);
+        if (newMemoryMaxUsage < memoryMaxUsage) {
+            fail(SubSystem.MEMORY, "getMemoryMaxUsage", memoryMaxUsage,
+                    newMemoryMaxUsage);
         }
 
-        if(newMemoryUsage < memoryUsage) {
-            fail(SubSystem.MEMORY, "getMemoryUsage", newMemoryUsage, memoryUsage);
+        if (newMemoryUsage < memoryUsage) {
+            fail(SubSystem.MEMORY, "getMemoryUsage", memoryUsage, newMemoryUsage);
         }
     }