fix: add channel release switch for drc

redis/redis-integration-test/src/test/java/com/ctrip/xpipe/redis/integratedtest/metaserver/proxy/LocalProxyConfig.java

@@ -91,6 +91,11 @@ public boolean isCompressEnabled() {
         return compress;
     }
 
+    @Override
+    public boolean allowCloseChannel() {
+        return true;
+    }
+
     @Override
     public CompressAlgorithm getCompressAlgorithm() {
         return new CompressAlgorithm() {

redis/redis-proxy/src/main/java/com/ctrip/xpipe/redis/proxy/config/DefaultProxyConfig.java

@@ -68,6 +68,8 @@ public class DefaultProxyConfig extends AbstractConfigBean implements ProxyConfi
 
     private static final String KEY_CROSS_REGION_TRAFFIC_CONTROL_LIMIT = "proxy.cross.region.traffic.control.limit";
 
+    private static final String ALLOW_CLOSE_CHANNEL = "proxy.allow.close.channel";
+
     public DefaultProxyConfig() {
         CompositeConfig compositeConfig = new CompositeConfig();
         compositeConfig.addConfig(Config.DEFAULT);
@@ -215,4 +217,9 @@ public boolean isCrossRegionTrafficControlEnabled() {
     public long getCrossRegionTrafficControlLimit() {
         return getLongProperty(KEY_CROSS_REGION_TRAFFIC_CONTROL_LIMIT, 200 * 1024 * 1024L); // 100MB/s default
     }
+
+    @Override
+    public boolean allowCloseChannel() {
+        return getBooleanProperty(ALLOW_CLOSE_CHANNEL, true);
+    }
 }

redis/redis-proxy/src/main/java/com/ctrip/xpipe/redis/proxy/config/ProxyConfig.java

@@ -61,4 +61,9 @@ public interface ProxyConfig extends TLSConfig {
      */
     long getCrossRegionTrafficControlLimit();
 
+    /**
+     * DRC does not allow the proxy to actively close the channel during backpressure.
+     * @return true if allowing the proxy to actively close the connection, false otherwise.
+     */
+    boolean allowCloseChannel();
 }

redis/redis-proxy/src/main/java/com/ctrip/xpipe/redis/proxy/tunnel/DefaultTunnel.java

@@ -236,10 +236,10 @@ protected void check() {
             long maxBlockWait = config.getBlockWaitBaseMill() + DefaultProxyServer.WRITE_HIGH_WATER_MARK / config.getBlockWaitRate();
             long localFrontendBlockFrom = frontendBlockFrom.get();
             long localBackendBlockFrom = backendBlockFrom.get();
-            if (localFrontendBlockFrom > 0 && current - localFrontendBlockFrom > maxBlockWait) {
+            if (localFrontendBlockFrom > 0 && current - localFrontendBlockFrom > maxBlockWait && config.allowCloseChannel()) {
                 logger.warn("[check][frontendLongBlock][{}] close", current - localFrontendBlockFrom);
                 frontend.release();
-            } else if (localBackendBlockFrom > 0 && current - localBackendBlockFrom > maxBlockWait) {
+            } else if (localBackendBlockFrom > 0 && current - localBackendBlockFrom > maxBlockWait && config.allowCloseChannel()) {
                 logger.warn("[check][backendLongBlock][{}] close", current - localBackendBlockFrom);
                 backend.release();
             }

redis/redis-proxy/src/test/java/com/ctrip/xpipe/redis/proxy/TestProxyConfig.java

@@ -186,4 +186,9 @@ public TestProxyConfig setStartMonitor(boolean startMonitor) {
     public void setCompress(boolean compress) {
         this.compress = compress;
     }
+
+    @Override
+    public boolean allowCloseChannel() {
+        return true;
+    }
 }