> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chainstream.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Data Freshness & SLA

> Latency, refresh intervals and backfill behaviour for every data product, per chain and per surface.

This page is the single source of truth for **how fresh** each data product is. If you're sizing a trading bot, a compliance alerting system or an agent feedback loop, these numbers are what matters.

## End-to-end latency model

```
[chain event] → [ingestion] → [normalization] → [Kafka] → [REST / WS / GraphQL cache]
        ~0            <200ms         <200ms         <500ms         +50–500ms
```

## Per-surface latency

| Surface         | Target p50 | Target p99 | Notes                                             |
| :-------------- | :--------- | :--------- | :------------------------------------------------ |
| Kafka Streams   | 800 ms     | 2 s        | Closest to source; used for low-latency pipelines |
| WebSocket       | 1.0 s      | 3 s        | Same source as Kafka; adds fan-out overhead       |
| REST (cached)   | 1.5 s      | 5 s        | Cache TTLs vary per endpoint — see each one       |
| REST (uncached) | 3 s        | 10 s       | Rare; for deep historical lookups                 |
| GraphQL         | 2 s        | 6 s        | Joins multiple products; adds planning time       |

## Per-product refresh

| Product                         | Real-time? | Snapshot cadence       |
| :------------------------------ | :--------- | :--------------------- |
| Tokens — market                 | yes        | price tick every trade |
| Tokens — security               | delayed    | minutes after creation |
| Trades                          | yes        | per block              |
| Pools                           | yes        | per event              |
| Wallets — holdings              | yes        | seconds after transfer |
| Wallets — net worth history     | no         | hourly                 |
| Candles (OHLC)                  | yes        | bar closes at interval |
| Holders (table)                 | yes        | per transfer           |
| Holders (distribution metrics)  | no         | every 5 min            |
| Smart Money (cohort membership) | no         | weekly (Mon 00:00 UTC) |
| Smart Money (flow events)       | yes        | per trade              |
| Blockchain Core                 | yes        | per block              |
| Rankings                        | yes (most) | 1 min / block-level    |
| Compliance (KYT / KYA)          | yes        | on request             |

## Backfill behaviour

* **Solana / EVM** archival data backfilled from genesis where feasible.
* **New chains** start with ≥ 30 days of backfill at launch, full history streamed in within the first 90 days.
* **Reorgs** cause rewrites of the affected slot/block in all downstream streams; consumers should be idempotent on `(chainId, txHash)` + `logIndex`.

## Incidents & status

Current incidents and historical uptime live at [status.chainstream.io](https://status.chainstream.io) (link to be finalized).

## Next

<CardGroup cols={2}>
  <Card title="Rate limits" icon="gauge" href="/en/docs/platform/billing-payments/plans-and-units">
    Per-plan throughput limits and headers.
  </Card>

  <Card title="Kafka topic catalog" icon="tower-broadcast" href="/en/api-reference/kafka-topics/evm">
    Exact topic names and retention per chain.
  </Card>
</CardGroup>