For the latest stable version, please use Korvet 0.19!

Storage Metrics

These metrics are emitted by every Korvet storage tier under the korvet.storage.* namespace. Each verb (read, write, ack) is recorded once per call and tagged with tier=local|remote, so the same dashboard query works across the local Redis tier and the remote Iceberg tier. The read timer additionally carries mode=stream|group to distinguish standalone reads from consumer-group reads.

Cross-Tier Verbs

Ack

Storage acknowledgement latency.

Name: korvet.storage.ack
Type: timer
Base unit: seconds

Table 1. Tags
Key	Description
`result`	Operation outcome (e.g. `success`, `empty`, `error`, `timeout`).
`tier`	Storage tier ( `local` or `remote`).

Read

Storage read latency. Tagged by mode=stream|group to distinguish direct stream reads from consumer-group reads (XREADGROUP, pending claims, autoclaim).

Name: korvet.storage.read
Type: timer
Base unit: seconds

Table 2. Tags
Key	Description
`mode`	Read mode ( `stream` for direct stream reads, `group` for consumer-group reads).
`result`	Operation outcome (e.g. `success`, `empty`, `error`, `timeout`).
`tier`	Storage tier ( `local` or `remote`).

Read Messages

Messages returned per read call. Tagged by mode=stream|group.

Name: korvet.storage.read.messages
Type: distribution summary
Base unit: messages

Table 3. Tags
Key	Description
`mode`	Read mode ( `stream` for direct stream reads, `group` for consumer-group reads).
`tier`	Storage tier ( `local` or `remote`).

Write

Storage write latency (writes, deletes, group admin).

Name: korvet.storage.write
Type: timer
Base unit: seconds

Table 4. Tags
Key	Description
`result`	Operation outcome (e.g. `success`, `empty`, `error`, `timeout`).
`tier`	Storage tier ( `local` or `remote`).

Write Messages

Messages written per write call.

Name: korvet.storage.write.messages
Type: distribution summary
Base unit: messages

Table 5. Tags
Key	Description
`tier`	Storage tier ( `local` or `remote`).

Local Tier (Redis)

Pool Acquire

Local Redis pool acquisition latency by result.

Name: korvet.storage.local.pool.acquire
Type: timer
Base unit: seconds

Table 6. Tags
Key	Description
`result`	Pool acquisition outcome ( `success`, `timeout`, `error`).

Pool Pending

Current number of pending waiters on the local Redis connection pool.

Name: korvet.storage.local.pool.pending
Type: gauge

Remote Tier (Parquet)

Remote-tier reads and writes flow through the shared cross-tier verbs above with tier=remote. There are no remote-specific commit or file-shape meters — each offloaded segment commits as one Iceberg append, so the existing korvet.storage.write / korvet.storage.read series describe remote behaviour. See Storage Worker Metrics for offload and retention activity against the remote tier.