Updated Canal prometheus (markdown)

Canal-prometheus.md

@@ -61,6 +61,7 @@ clamp_max(rate(canal_instance_sink_blocking_time{destination="example"}[2m]), 10
 _简单说明一下range-vector,通俗来说表达式会用时间点前range-vector period内的所有samples参与运算。_
 _range-vector值如果太小，图会碎片化；反之，实时性会比较差，不能及时反应变化。请结合scrape_interval设定合理的值。_
 
+
 * Dump线程空闲比
 ```
 clamp_max(rate(canal_instance_publish_blocking_time{destination="example"}[2m]), 1000) / 10
@@ -71,6 +72,7 @@ clamp_max(rate(canal_instance_publish_blocking_time{destination="example"}[2m]),
 
 **2. Sinking idle ratio较低，那么server端parser是性能瓶颈，可参考[Performance](https://github.com/alibaba/canal/wiki/Performance)进行tuning.**
 
+
 * Delay(seconds)
 ```
 canal_instance_traffic_delay / 1000
@@ -81,18 +83,21 @@ canal_instance_traffic_delay / 1000
 
 **2. Limitations: 如果store满了(恰好store中的数据包含最新的position，且MySQL binlog停止更新)，且client暂停消费，那么delay会不断增长。当然，满足这些条件的概率极低。**
 
+
 * Binlog接收带宽(KB/s)
 ```
 rate(canal_instance_received_binlog_bytes{destination="example"}[2m]) / 1024
 ```
 **'Sink线程空闲比'与'Dump线程空闲比'都很低，delay还是很高的情况，请查看binlog接收速率是否符合预期。**
 
+
 * TPS(Binlog events)
 ```
 rate(canal_instance_store_consume_seq{destination="example"}[2m])
 ```
 **Canal instance client消费TPS(以binlog event为单位)，即canal instance最终的整体性能。**
 
+
 * Client消费带宽(KB/s)
 ```
 rate(canal_instance_client_bytes{destination="example"}[2m]) / 1024
@@ -101,36 +106,42 @@ rate(canal_instance_client_bytes{destination="example"}[2m]) / 1024
 
 **注意：client在binlog无更新时busy poll，所占用的带宽也是颇为可观的，如上图。**
 
+
 * TPS(MySQL transaction)
 ```
 rate(canal_instance_transactions{destination="example"}[2m])
 ```
 **Canal instance处理transaction的TPS，以TRANSACTION_END事件为基准。**
 
+
 * TPS(Table row)
 ```
 rate(canal_instance_rows_counter{destination="example"}[2m])
 ```
 **Canal instance接受binlog中，数据库表变更行数的TPS.**
 
+
 * DML model indicator
 ```
 rate(canal_instance_rows_counter{destination="example"}[15s]) / rate(canal_instance_row_events{destination="example"}[15s])
 ```
 **RowData events包含行数。OLTP下，RowData大体上仅包含1行变更；批量DML下，该指标会上行。**
 
+
 * RPS(Client request)
 ```
 rate(canal_instance_client_packets{destination="example"}[2m])
 ```
 **Netty server处理client requests吞吐量。**
 
+
 * QPS(空包)
 ```
 rate(canal_instance_client_empty_batches{destination="example"}[2m])
 ```
 **client get返回每秒空包量。如果正常traffic下，该值很大，考虑使用connector的timeout机制，节省资源。**
 
+
 * Client latency
 
 _experimental_
@@ -139,18 +150,21 @@ canal_instance_client_request_latency_bucket
 ```
 **Histogram, client请求响应情况。关于[histogram](https://prometheus.io/docs/concepts/metric_types/#histogram).**
 
+
 * Event store占用
 ```
 canal_instance_store_produce_seq - canal_instance_store_consume_seq
 ```
 **Event store内未ack的events数量，实时性受scrape_interval影响。**
 
+
 * Event store memory占用(KB, 仅memory mode)
 ```
 (canal_instance_store_produce_mem - canal_instance_store_consume_mem) / 1024
 ```
 **Event store内未ack的events所占用内存大小，实时性受scrape_interval影响。**
 
+
 * 状态信息
 ```
 canal_instance