Introduce Keyspace

[ystaticy]

Feature Request

Is your feature request related to a problem? Please describe:

RFC: #39685

Describe the feature you'd like:

If keyspace-name is set, the TiDB node will use API V2 to reading and writing TiKV data.
Different keyspaces have their own prefixes. So we can separate data by prefix.

Describe alternatives you've considered:

Teachability, Documentation, Adoption, Migration Strategy:

• Keyspace implement in TiDB:

  • keyspace: introduce keyspace conf and etcd path #40269
  • br: adaption for keyspace feature #40532
  • lightning: local backend support keyspace #40628
  • keyspace: gc delete range #40639
  • metrics: attach const label keyspace_id #41693
  • support keyspace label in TiDB grafana
  • TiDB GC Worker support GC V2

• Keyspace implement in TiDB Data import and export:

  • TiDB Binlog
  • TiDB CDC
  • [DNM]dumpling: Support check keyspace in dumpling #53541

• Keyspace implement in PD:

  • implement keyspace management tikv/pd#5293 @AmoebaProtozoa
  • GC V2 interfaces tikv/pd#7500

• Keyspace implement in TiKV and client-go:

  • [WIP]KeySpace Implement tikv/tikv#12999

• Keyspace implement in TiFlash:

  • support keyspace feature tiflash#6816
  • Fix sync schema after schema version key be removed tiflash#7072
  • GC V2: Support different gc_safepoint for different keyspace tiflash#7684

• Keyspace level GC:

  • [WIP]GC: support BR,Lightning,Dumpling update Service SafePoint with GCManagementType #53303