table manager does not purge chunk in loki 2.4

I wanted to have a deletion of chunk data older than 31 days so I made such config

schema_config:
  configs:
    - from: 2020-10-24
      store: boltdb-shipper
      object_store: filesystem
      schema: v11
      index:
        prefix: index_
        period: 24h

storage_config:
  boltdb_shipper:
    active_index_directory: "/var/lib/loki/boltdb-shipper-active"
    cache_location: "/var/lib/loki/boltdb-shipper-cache"
    cache_ttl: 24h 
    shared_store: filesystem
  filesystem:
    directory: /var/lib/loki/chunks

chunk_store_config:
  max_look_back_period: 0s

table_manager:
  retention_deletes_enabled: true
  retention_period: 31d

but actually the deletion never happen.

did I forget something in the configuration ?

loki version: 2.4.1

Solution 1:

I'm not sure it's your case, but starting on the Loki 2.4.0, the single binary no longer runs a table-manager, this impacts anyone in the following scenarios:

1. Running a single binary Loki with any index type other than boltdb-shipper or boltdb
2. Relying on retention with the configs retention_deletes_enabled and retention_period

See more info and how to resolve this issue, in the Loki Upgrade Guide, here.

Solution 2:

Retention in Grafana Loki is achieved either through the Table Manager or the Compactor. In your case, boltdb-shipper is used for index and chunks. Table manager isn't a great choice when it comes to local storage.

The Compactor retention will become the default and have a long-term support. It supports more granular retention policies on per tenant and per stream use cases.

Please kindly check the Guide here

compactor:
  retention_enabled: true
  retention_delete_delay: 2h <amount of hours to delay the retention period>
  retention_delete_worker_count: 150
limits_config:
  retention_period: [30d]