Data Lifecycle. Time To Live (TTL)

Time To Live (TTL) is a mechanism to automatically delete data that is older than the specified time.

In SkyWalking, there are two types of observability data:

1. Records include traces, logs, topN sampled statements and alarm. recordDataTTL applies to record data.
2. Metrics include all metrics for service, instance, endpoint, and topology map. Metadata(lists of services, instances, or endpoints) also belongs to metrics. metricsDataTTL applies to Metrics data.

These are the settings for the different types:

    # Set a timeout on metrics data. After the timeout has expired, the metrics data will automatically be deleted.
    recordDataTTL: ${SW_CORE_RECORD_DATA_TTL:3} # Unit is day
    metricsDataTTL: ${SW_CORE_METRICS_DATA_TTL:7} # Unit is day

BanyanDB TTL

BanyanDB has a TTL mechanism to automatically delete data that is older than the specified time. When you use BanyanDB as the storage backend, recordDataTTL and metricsDataTTL are not used. Instead, you should configure the TTL settings in storage.banyandb.

Please refer to the Storage BanyanDB and BanyanDB's Progressive TTL documents for more information.