pd: update pd alert rules

alert-rules.md

@@ -244,7 +244,7 @@ This section gives the alert rules for the PD component.
     * If you confirm that the TiKV/TiFlash instance cannot be recovered, you can make it offline.
     * If you confirm that the TiKV/TiFlash instance can be recovered, but not in the short term, you can consider increasing the value of `max-down-time`. It will prevent the TiKV/TiFlash instance from being considered as irrecoverable and the data from being removed from the TiKV/TiFlash.
 
-#### `PD_cluster_unhealthy_tikv_nums`
+#### `PD_cluster_unhealthy_store_nums`
 
 * Alert rule:
 
@@ -256,7 +256,7 @@ This section gives the alert rules for the PD component.
 
 * Solution:
 
-    Check the state of the TiKV stores.
+    Check the status of TiKV/TiFlash.
 
 #### `PD_cluster_low_space`
 
@@ -355,7 +355,7 @@ This section gives the alert rules for the PD component.
     * Check the network and system load status.
     * If the problematic PD instance cannot be recovered due to environmental factors, make it offline and replace it.
 
-#### `TiKV_space_used_more_than_80%`
+#### `PD_cluster_store_space_used_more_than_80%`
 
 * Alert rule:
 
@@ -384,21 +384,6 @@ This section gives the alert rules for the PD component.
 
     Check whether the system time is configured correctly.
 
-#### `PD_no_store_for_making_replica`
-
-* Alert rule:
-
-    `increase(pd_checker_event_count{type="replica_checker", name="no_target_store"}[1m]) > 0`
-
-* Description:
-
-    There is no appropriate store for additional replicas.
-
-* Solution:
-
-    * Check whether there is enough space in the store.
-    * Check whether there is any store for additional replicas according to the label configuration if it is configured.
-
 #### `PD_cluster_slow_tikv_nums`
 
 * Alert rule: