rebase and cherry-pick, add pressure test report.

discovery/aliyun/README.md

@@ -0,0 +1,61 @@
+## Aliyun ECS service discovery config
+
+### prometheus-example.yml
+
+```yaml
+global:
+  scrape_interval: 15s
+  scrape_timeout: 10s
+  evaluation_interval: 30s
+scrape_configs:
+  - job_name: _aliyun-prom/ecs-sd
+    honor_timestamps: true
+    scrape_interval: 30s
+    scrape_timeout: 10s
+    metrics_path: /metrics
+    scheme: https
+    ecs_sd_configs:
+      - port: 8888 # Prometheus crawling collection point port after service discovery
+        user_id: <aliyun userId> # Aliyun user id, optional, filling this in will add the label __meta_ecs_user_id to the discovery target.
+        refresh_interval: 30s
+        region_id: cn-hangzhou # the region of ecs
+        access_key: <aliyun ak> # Aliyun AccessKeyID
+        access_key_secret: <aliyun sk> # Aliyun AccessKeySecret
+        tag_filters: # Aliyun ECS tag filter
+          - key: "testK"
+            values: ["*", "test1*"]
+          - key: "testM"
+            values: ["test2*"]
+        limit: 100 # The maximum number of instances to query, default value is 100, get all instances when less than zero.
+
+    # Optional, for manual screening of instances
+    relabel_configs:
+      # 1. Manually set the IP address of the ECS
+      #    By default, the ECS will search and assign the collection IP to this ECS in the order of
+      #    classic network public IP > classic network private IP > VPC network public IP > VPC network private IP.
+      #    The collection point port is set by aliyun_sd_configs.port.
+      - source_labels: [__meta_ecs_public_ip] # classic network public IP
+        #   - source_labels: [__meta_ecs_inner_ip]       # classic network private IP
+        #   - source_labels: [__meta_ecs_eip]            # VPC network public IP
+        #   - source_labels: [__meta_ecs_private_ip]     # VPC network private IP
+        regex: (.*)
+        target_label: __address__
+        replacement: $1:<port> # Set the collection port when relabeling
+
+
+      # 2. Filter by ECS attribute
+      #    [keep] means only keep the target filtered by this condition,
+      #    [drop] means filter out the target filtered by this condition.
+      #     __meta_ecs_instance_id          instance id
+      #     __meta_ecs_region_id            instance region, Note that aliyun_sd_configs.region_id in the configuration determines the region of the ECS query
+      #     __meta_ecs_status               instance status, including Running, Starting, Stopping and Stopped
+      #     __meta_ecs_zone_id              instance zone id
+      #     __meta_ecs_network_type         instance network type, including  classic and vpc
+      #     __meta_ecs_tag_<TagKey>         instance tag
+      #
+      # - source_labels:  ["__meta_ecs_instance_id"]
+      #   regex: ".+"       # or other value regex
+      #   action: keep      # keep / drop
+```
+
+### [Pressure Test](./PRESSURE_TEST.md)