General Notes Cortex has evolved over several years, and the command-line options sometimes reflect this heritage. In some cases the default value for options is not the recommended value, and in some cases names do not reflect the true meaning. We do intend to clean this up, but it requires a lot of care to avoid breaking existing installations. In the meantime we regret the inconvenience. Duration arguments should be specified with a unit like 5s or 3h.| Cortex
The querier service handles queries using the PromQL query language. This document dives into the storage-specific details of the querier service. The general architecture documentation applies too. The querier is stateless. How it works The querier needs to have an almost up-to-date view over the entire storage bucket, in order to find the right blocks to lookup at query time. The querier can keep the bucket view updated in to two different ways:| Cortex
The store-gateway is the Cortex service responsible to query series from blocks. The store-gateway is required when running the Cortex blocks storage. The store-gateway is semi-stateful. How it works The store-gateway needs to have an almost up-to-date view over the storage bucket, in order to discover blocks belonging to their shard. The store-gateway can keep the bucket view updated in to two different ways: Periodically scanning the bucket (default) Periodically downloading the bucket inde...| Cortex
The compactor is an service which is responsible to: Compact multiple blocks of a given tenant into a single optimized larger block. This helps to reduce storage costs (deduplication, index size reduction), and increase query speed (querying fewer blocks is faster). Keep the per-tenant bucket index updated. The bucket index is used by queriers, store-gateways and rulers to discover new blocks in the storage. The compactor is stateless. How compaction works The blocks compaction has two main b...| Cortex
The bucket index is a per-tenant file containing the list of blocks and block deletion marks in the storage. The bucket index itself is stored in the backend object storage, is periodically updated by the compactor, and used by queriers, store-gateways and rulers to discover blocks in the storage. The bucket index usage is optional and can be enabled via -blocks-storage.bucket-store.bucket-index.enabled=true (or its respective YAML config option). Benefits The querier, store-gateway and ruler...| Cortex