diff --git a/src/org/redkale/source/DataSqlSource.java b/src/org/redkale/source/DataSqlSource.java
index 693a65a43..22dbb2588 100644
--- a/src/org/redkale/source/DataSqlSource.java
+++ b/src/org/redkale/source/DataSqlSource.java
@@ -89,7 +89,7 @@ public abstract class DataSqlSource<DBChannel> extends AbstractService implement
             t.setUncaughtExceptionHandler(ueh);
             return t;
         });
-        final int bufferCapacity = Integer.decode(readprop.getProperty(JDBC_CONNECTIONSCAPACITY, "" + 16 * 1024));
+        final int bufferCapacity = Math.max(16 * 1024, Integer.decode(readprop.getProperty(JDBC_CONNECTIONSCAPACITY, "" + 16 * 1024)));
         this.bufferPool = new ObjectPool<>(new AtomicLong(), new AtomicLong(), this.threads,
             (Object... params) -> ByteBuffer.allocateDirect(bufferCapacity), null, (e) -> {
                 if (e == null || e.isReadOnly() || e.capacity() != bufferCapacity) return false;