fixed fixed for large datasource test in small memory

src/test/java/com/alibaba/druid/bvt/pool/Large10ConcurrentTest.java

@@ -1,5 +1,6 @@
 package com.alibaba.druid.bvt.pool;
 
+import java.lang.management.ManagementFactory;
 import java.sql.Connection;
 import java.sql.SQLException;
 import java.util.concurrent.CountDownLatch;
@@ -19,12 +20,25 @@ import com.alibaba.druid.util.JdbcUtils;
 
 public class Large10ConcurrentTest extends TestCase {
 
-    private DruidDataSource[]        dataSources = new DruidDataSource[10000];
+    private DruidDataSource[]        dataSources;
     private ScheduledExecutorService scheduler;
 
     private ExecutorService          executor;
 
     protected void setUp() throws Exception {
+        long xmx = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage().getMax() / (1000 * 1000); // m
+        
+        final int dataSourceCount;
+        if (xmx <= 500) {
+            dataSourceCount = 500;
+        } else if (xmx <= 1000) {
+            dataSourceCount = 1000;
+        } else {
+            dataSourceCount = 10000;
+        }
+        
+        dataSources = new DruidDataSource[10000];
+        
         executor = Executors.newFixedThreadPool(100);
         scheduler = Executors.newScheduledThreadPool(10);
         for (int i = 0; i < dataSources.length; ++i) {