[dubbo] 12/45: improve:修复大并发时，Netty io 导致的 CPU 占用过高问题

[li...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

liujun pushed a commit to branch release/3.0.14-rpccontext-bugfix
in repository https://gitbox.apache.org/repos/asf/dubbo.git

commit aad5c91d191585cfb3c433b3d1d1cd31c2ada2a3
Author: 未宇 <li...@alibaba-inc.com>
AuthorDate: Mon Oct 12 16:39:38 2020 +0800

    improve:修复大并发时，Netty io 导致的 CPU 占用过高问题
---
 .../dubbo/remoting/transport/AbstractServer.java     |  3 +--
 .../dubbo/remoting/transport/netty4/NettyServer.java | 20 +++++++++++---------
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/transport/AbstractServer.java b/dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/transport/AbstractServer.java
index ef448db..967d8d2 100644
--- a/dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/transport/AbstractServer.java
+++ b/dubbo-remoting/dubbo-remoting-api/src/main/java/org/apache/dubbo/remoting/transport/AbstractServer.java
@@ -172,8 +172,7 @@ public abstract class AbstractServer extends AbstractEndpoint implements Remotin
             return;
         }
 
-        Collection<Channel> channels = getChannels();
-        if (accepts > 0 && channels.size() > accepts) {
+        if (accepts > 0 && getChannels().size() > accepts) {
             logger.error("Close channel " + ch + ", cause: The server " + ch.getLocalAddress() + " connections greater than max config " + accepts);
             ch.close();
             return;
diff --git a/dubbo-remoting/dubbo-remoting-netty4/src/main/java/org/apache/dubbo/remoting/transport/netty4/NettyServer.java b/dubbo-remoting/dubbo-remoting-netty4/src/main/java/org/apache/dubbo/remoting/transport/netty4/NettyServer.java
index 9c4f1b8..3a2aa5d 100644
--- a/dubbo-remoting/dubbo-remoting-netty4/src/main/java/org/apache/dubbo/remoting/transport/netty4/NettyServer.java
+++ b/dubbo-remoting/dubbo-remoting-netty4/src/main/java/org/apache/dubbo/remoting/transport/netty4/NettyServer.java
@@ -40,8 +40,8 @@ import io.netty.channel.EventLoopGroup;
 import io.netty.handler.timeout.IdleStateHandler;
 
 import java.net.InetSocketAddress;
+import java.util.ArrayList;
 import java.util.Collection;
-import java.util.HashSet;
 import java.util.Map;
 
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
@@ -166,14 +166,16 @@ public class NettyServer extends AbstractServer implements RemotingServer {
 
     @Override
     public Collection<Channel> getChannels() {
-        Collection<Channel> chs = new HashSet<Channel>();
-        for (Channel channel : this.channels.values()) {
-            if (channel.isConnected()) {
-                chs.add(channel);
-            } else {
-                channels.remove(NetUtils.toAddressString(channel.getRemoteAddress()));
-            }
-        }
+        Collection<Channel> chs = new ArrayList<>(this.channels.size());
+        chs.addAll(this.channels.values());
+        //复用 NettyServerHandler 里面的 channels，所以不再需要检查是否可连
+//        for (Channel channel : this.channels.values()) {
+//            if (channel.isConnected()) {
+//                chs.add(channel);
+//            } else {
+//                channels.remove(NetUtils.toAddressString(channel.getRemoteAddress()));
+//            }
+//        }
         return chs;
     }