Latency and freshness
How to interpret timestamps, slot cadence, and freshness fields.
Polaris Market Data payloads include timestamps and slot fields so clients can make freshness decisions explicitly.
Common fields
| Field | Meaning |
|---|---|
processed_at_ms | Time the event was processed for customer delivery |
slot | Solana slot associated with the source event when available |
current_slot | Latest slot used to publish a slot-cadenced book |
source_age_ms | Age of the source data at publication time |
slot_lag | Difference between the current slot and a pool's last update slot |
Cadence
swaps, quote_surface, and depth are immediate event streams.
liquidity_book is slot-cadenced. It emits a grouped snapshot from the latest eligible pool state
on the slot cadence.
Stale data
Per-pool freshness is exposed in liquidity_book.pools. Clients should treat the aggregate book and
individual pool books separately: a pool can be stale while the aggregate book remains live.