# Schedules types

+ BALANCE
  + Leader
  + Regions 
+ Hot region
  + Write hot spots
  + Read hot 
+ cluster topology
+ Region merge

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Schedules types

BALANCE
  Distribute Region evenly across all Stores in the cluster. It can be divided into 2 types:
    1. The leader pays attention to the leader of the region, and can be thought of as the purpose of spreading the pressure of processing client request.
    2. The region focuses on the peers in the region in order to spread the stress of storage while avoiding full disks.

Hot region
  For write hotspots, hotspot scheduling attempts to break both the peer and leader of the hotspot region; for read hotspots, since only the leader carries the read pressure, the hotspot scheduling attempts to break the leader of the hotspot region. Please refer to the following sections for details.

cluster topology
  The topology for making PD aware of the distribution of different nodes is to ensure high availability and disaster recovery by scheduling individual replicas in different regions as possible. For example, if a cluster has 3 data centers, the safest way to schedule is to place the 3 peers of the region in different data centers, so that if any data center fails, it can continue to provide services.

Region merge
  Region merge refers to the process of merging adjacent small regions by scheduling in order to avoid large numbers of small regions or even empty regions consuming system resources after deleting data.