diff --git a/src/org/redkale/net/AsyncConnection.java b/src/org/redkale/net/AsyncConnection.java
index 33113ab81..b13a7ea20 100644
--- a/src/org/redkale/net/AsyncConnection.java
+++ b/src/org/redkale/net/AsyncConnection.java
@@ -12,6 +12,7 @@ import java.nio.channels.*;
 import java.util.*;
 import java.util.concurrent.*;
 import java.util.concurrent.atomic.AtomicLong;
+import java.util.function.Consumer;
 import javax.net.ssl.SSLContext;
 import static org.redkale.net.ProtocolServer.*;
 
@@ -40,6 +41,8 @@ public abstract class AsyncConnection implements AsynchronousByteChannel, AutoCl
     //关闭数
     protected AtomicLong closedCounter;
 
+    protected Consumer<AsyncConnection> beforeCloseListener;
+
     public final long getLastReadTime() {
         return readtime;
     }
@@ -89,6 +92,11 @@ public abstract class AsyncConnection implements AsynchronousByteChannel, AutoCl
         }
     }
 
+    public AsyncConnection beforeCloseListener(Consumer<AsyncConnection> beforeCloseListener) {
+        this.beforeCloseListener = beforeCloseListener;
+        return this;
+    }
+
     @Override
     public void close() throws IOException {
         if (closedCounter != null) {
@@ -99,6 +107,7 @@ public abstract class AsyncConnection implements AsynchronousByteChannel, AutoCl
             livingCounter.decrementAndGet();
             livingCounter = null;
         }
+        if (beforeCloseListener != null) beforeCloseListener.accept(this);
         if (attributes == null) return;
         try {
             for (Object obj : attributes.values()) {
diff --git a/src/org/redkale/source/DataSqlSource.java b/src/org/redkale/source/DataSqlSource.java
index 2a0000104..5ea7a10a0 100644
--- a/src/org/redkale/source/DataSqlSource.java
+++ b/src/org/redkale/source/DataSqlSource.java
@@ -95,12 +95,6 @@ public abstract class DataSqlSource<Conn> extends AbstractService implements Dat
 
     protected abstract PoolSource<Conn> createWritePoolSource(DataSource source, String stype, Properties prop);
 
-    @Local
-    protected abstract void closeReadConnection(final Conn conn);
-
-    @Local
-    protected abstract void closeWriteConnection(final Conn conn);
-
     @Override
     protected ExecutorService getExecutor() {
         return executor;
diff --git a/src/org/redkale/source/PoolJdbcSource.java b/src/org/redkale/source/PoolJdbcSource.java
index ed89aef66..a1ae4ec18 100644
--- a/src/org/redkale/source/PoolJdbcSource.java
+++ b/src/org/redkale/source/PoolJdbcSource.java
@@ -250,6 +250,16 @@ public class PoolJdbcSource extends PoolSource<Connection> {
         }
     }
 
+    @Override
+    public void closeConnection(final Connection conn) {
+        if (conn == null) return;
+        try {
+            conn.close();
+        } catch (Exception e) {
+            logger.log(Level.WARNING, "closeSQLConnection abort", e);
+        }
+    }
+
     @Override
     public Connection poll() {
         return poll(0, null);
diff --git a/src/org/redkale/source/PoolSource.java b/src/org/redkale/source/PoolSource.java
index c50242167..1c5c96df6 100644
--- a/src/org/redkale/source/PoolSource.java
+++ b/src/org/redkale/source/PoolSource.java
@@ -70,7 +70,7 @@ public abstract class PoolSource<T> {
         this.connectTimeoutSeconds = Integer.decode(prop.getProperty(JDBC_CONNECTTIMEOUT_SECONDS, "3"));
         this.readTimeoutSeconds = Integer.decode(prop.getProperty(JDBC_READTIMEOUT_SECONDS, "3"));
         this.writeTimeoutSeconds = Integer.decode(prop.getProperty(JDBC_WRITETIMEOUT_SECONDS, "3"));
-        this.maxconns = Integer.decode(prop.getProperty(JDBC_CONNECTIONSMAX, "" + Runtime.getRuntime().availableProcessors() * 16));
+        this.maxconns = Math.max(8, Integer.decode(prop.getProperty(JDBC_CONNECTIONSMAX, "" + Runtime.getRuntime().availableProcessors() * 16)));
         String dbtype0 = "";
         { //jdbc:mysql:// jdbc:microsoft:sqlserver:// 取://之前的到最后一个:之间的字符串
             int pos = this.url.indexOf("://");
@@ -141,6 +141,8 @@ public abstract class PoolSource<T> {
 
     public abstract void close();
 
+    public abstract void closeConnection(final T conn);
+
     public final String getDbtype() {
         return dbtype;
     }
diff --git a/src/org/redkale/source/PoolTcpSource.java b/src/org/redkale/source/PoolTcpSource.java
index 0eef340c5..7e71536af 100644
--- a/src/org/redkale/source/PoolTcpSource.java
+++ b/src/org/redkale/source/PoolTcpSource.java
@@ -8,10 +8,10 @@ package org.redkale.source;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.channels.*;
-import java.sql.SQLException;
+import java.sql.*;
 import java.util.Properties;
 import java.util.concurrent.*;
-import java.util.logging.Logger;
+import java.util.logging.*;
 import org.redkale.net.AsyncConnection;
 import org.redkale.util.ObjectPool;
 
@@ -30,6 +30,8 @@ public abstract class PoolTcpSource extends PoolSource<AsyncConnection> {
     //TCP Channel组
     protected AsynchronousChannelGroup group;
 
+    protected final ArrayBlockingQueue<AsyncConnection> connQueue;
+
     public PoolTcpSource(String rwtype, Properties prop, Logger logger, ObjectPool<ByteBuffer> bufferPool, ThreadPoolExecutor executor) {
         super(rwtype, prop, logger);
         this.bufferPool = bufferPool;
@@ -39,6 +41,19 @@ public abstract class PoolTcpSource extends PoolSource<AsyncConnection> {
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
+        this.connQueue = new ArrayBlockingQueue<>(this.maxconns);
+    }
+
+    @Override
+    public void closeConnection(final AsyncConnection conn) {
+        if (conn == null) return;
+        if (connQueue.offer(conn)) {
+            saveCounter.incrementAndGet();
+            usingCounter.decrementAndGet();
+        } else {
+            //usingCounter 会在close方法中执行
+            conn.dispose();
+        }
     }
 
     @Override
@@ -52,7 +67,40 @@ public abstract class PoolTcpSource extends PoolSource<AsyncConnection> {
 
     @Override
     public CompletableFuture<AsyncConnection> pollAsync() {
+        return pollAsync(0);
+    }
+
+    protected CompletableFuture<AsyncConnection> pollAsync(final int count) {
+        if (count >= 3) {
+            logger.log(Level.WARNING, "create datasource connection error");
+            CompletableFuture<AsyncConnection> future = new CompletableFuture<>();
+            future.completeExceptionally(new SQLException("create datasource connection error"));
+            return future;
+        }
+        AsyncConnection conn0 = connQueue.poll();
+        if (conn0 != null) {
+            cycleCounter.incrementAndGet();
+            usingCounter.incrementAndGet();
+            return CompletableFuture.completedFuture(conn0);
+        }
+        if (usingCounter.get() >= maxconns && count < 2) {
+            return CompletableFuture.supplyAsync(() -> {
+                try {
+                    return connQueue.poll(3, TimeUnit.SECONDS);
+                } catch (Exception t) {
+                    return null;
+                }
+            }, executor).thenCompose((conn2) -> {
+                if (conn2 != null) {
+                    cycleCounter.incrementAndGet();
+                    return CompletableFuture.completedFuture(conn2);
+                }
+                return pollAsync(count + 1);
+            });
+        }
+
         return AsyncConnection.createTCP(group, this.servaddr, this.readTimeoutSeconds, this.writeTimeoutSeconds).thenCompose(conn -> {
+            conn.beforeCloseListener((c) -> usingCounter.decrementAndGet());
             CompletableFuture<AsyncConnection> future = new CompletableFuture();
             final ByteBuffer buffer = reqConnectBuffer(conn);
             conn.write(buffer, null, new CompletionHandler<Integer, Void>() {
@@ -95,6 +143,21 @@ public abstract class PoolTcpSource extends PoolSource<AsyncConnection> {
                 }
             });
             return future;
+        }).whenComplete((c, t) -> {
+            if (t == null) {
+                creatCounter.incrementAndGet();
+                usingCounter.incrementAndGet();
+            }
+        });
+    }
+
+    @Override
+    public void close() {
+        connQueue.stream().forEach(x -> {
+            try {
+                x.close();
+            } catch (Exception e) {
+            }
         });
     }
 }