Improved test case

h2/src/test/org/h2/test/db/TestMemoryUsage.java

@@ -177,11 +177,16 @@ public class TestMemoryUsage extends TestBase {
         }
         int base = Utils.getMemoryUsed();
         stat.execute("create index idx_test_id on test(id)");
-        System.gc();
-        System.gc();
-        int used = Utils.getMemoryUsed();
-        if ((used - base) > getSize(7500, 12000)) {
-            fail("Used: " + (used - base));
+        for (int i = 0;; i++) {
+            System.gc();
+            int used = Utils.getMemoryUsed() - base;
+            if (used <= getSize(7500, 12000)) {
+                break;
+            }
+            if (i < 16) {
+                continue;
+            }
+            fail("Used: " + used);
         }
         stat.execute("drop table test");
         conn.close();