diff --git a/gopher_tech.md b/gopher_tech.md
index 82868471a0e9f3179c750b292dc47c76ab7457db..aed7b113823692ede982c5f95309fa44fa69c330 100644
--- a/gopher_tech.md
+++ b/gopher_tech.md
@@ -23,8 +23,9 @@
 | rcv_space           | tcp_rate    | Gauge        |                    |      | Current   receive buffer size.                               |
 | notsent_bytes       | tcp_windows | Gauge        | bytes              |      | Number   of bytes not sent currently.                        |
 | notack_bytes        | tcp_windows | Gauge        | bytes              |      | Number   of bytes not ack currently.                         |
-| snd_wnd             | tcp_windows | Gauge        |                    |      | Size   of TCP send window.                                   |
-| rcv_wnd             | tcp_windows | Gauge        |                    |      | Size   of TCP receive window.                                |
+| snd_wnd             | tcp_windows | Gauge        |                    |      | Size of TCP send window.                                     |
+| rcv_wnd             | tcp_windows | Gauge        |                    |      | Size of TCP receive window.                                  |
+| avl_snd_wnd         | tcp_windows | Gauge        |                    |      | Size of TCP available send window.                           |
 | delivery_rate       | tcp_rate    | Gauge        |                    |      | Current   transmit rate (multiple different from the actual value). |
 | busy_time           | tcp_rate    | Gauge        |                    |      | Time   (jiffies) busy sending data.                          |
 | rwnd_limited        | tcp_rate    | Gauge        |                    |      | Time   (jiffies) limited by receive window.                  |
@@ -45,9 +46,9 @@
 | segs_out            | tcp_tx_rx   | Counter      | segs               |      | total   number of segments sent                              |
 | retran_packets      | tcp_abn     | Gauge        |                    | Y    | total number of retrans                                      |
 | backlog_drops       | tcp_abn     | Gauge        |                    | Y    | drops   caused by backlog queue full                         |
-| sk_drops            | tcp_abn     | Counter      |                    | Y    | tcp   drop counter                                           |
-| lost_out            | tcp_abn     | Gauge        |                    |      | tcp   lost counter                                           |
-| sacked_out          | tcp_abn     | Gauge        |                    |      | tcp   sacked out counter                                     |
+| sk_drops            | tcp_abn     | Counter      |                    | Y    | Number of lost packets in the TCP protocol stack             |
+| lost_out            | tcp_abn     | Gauge        | segs               |      | Number of lost segments estimated by TCP congestion          |
+| sacked_out          | tcp_abn     | Gauge        | segs               |      | Number of out-of-order TCP packets (SACK) or number of repeated TCP ACKs (NO SACK) |
 | filter_drops        | tcp_abn     | Gauge        |                    |      | drops   caused by socket filter                              |
 | tmout_count         | tcp_abn     | Gauge        |                    |      | counter   of tcp link timeout                                |
 | snd_buf_limit_count | tcp_abn     | Gauge        |                    |      | counter   of limits when allocate wmem                       |
diff --git a/gopher_tech_abnormal.md b/gopher_tech_abnormal.md
index 41f675af2647ee1e554faaf06f751b48c17c6df1..93a04402e53496690b712ef7d9adf0f060a0040c 100644
--- a/gopher_tech_abnormal.md
+++ b/gopher_tech_abnormal.md
@@ -69,12 +69,18 @@ gala-gopher提供系统异常检测能力，支持用户在启动各个探针的
 
 ### TCP_LINK
 
-| 异常事件名    | 事件信息                                   | 输出参数          | 输入参数 | 异常等级 |
-| ------------- | ------------------------------------------ | ----------------- | -------- | -------- |
-| tcp_oom       | TCP out of memory(%u).                     | P1: error count   | NA       | WARN     |
-| backlog_drops | TCP backlog queue drops(%u).               | P1: drops count   | [-D <>]  | WARN     |
-| filter_drops  | TCP filter drops(%u).                      | P1: drops count   | [-D <>]  | WARN     |
-| syn_srtt      | TCP connection establish timed out(%u us). | P1: syn rtt times | [-T <>]  | WARN     |
+| 异常事件名    | 事件信息                                                     | 输出参数          | 输入参数 | 异常等级 |
+| ------------- | ------------------------------------------------------------ | ----------------- | -------- | -------- |
+| tcp_oom       | TCP out of memory(%u).                                       | P1: error count   | NA       | WARN     |
+| backlog_drops | TCP backlog queue drops(%u).                                 | P1: drops count   | [-D <>]  | WARN     |
+| filter_drops  | TCP filter drops(%u).                                        | P1: drops count   | [-D <>]  | WARN     |
+| syn_srtt      | TCP connection establish timed out(%u us).                   | P1: syn rtt times | [-T <>]  | WARN     |
+| sk_drops      | Number of lost packets in the TCP protocol stack(%u).        | P1: drops count   | [-D <>]  | WARN     |
+| lost_out      | Number of lost segments estimated by TCP congestion(%u).     | P1: drops count   | [-D <>]  | WARN     |
+| sacked_out    | Number of out-of-order TCP packets (SACK) or number of repeated TCP ACKs (NO SACK)(%u). | P1: drops count   | [-D <>]  | WARN     |
+| rcv_wnd       | TCP zero receive windows.                                    | NA                | NA       | WARN     |
+| snd_wnd       | TCP zero send windows.                                       | NA                | NA       | WARN     |
+| avl_snd_wnd   | TCP zero available send windows.                             | NA                | NA       | WARN     |
 
 > 注：输入参数为NA表示不需要外部输入阈值参数，内部实现是根据指标值是否为0判断异常与否。