[Yandex Cloud documentation](../../index.md) > [Monium](../index.md) > [Traces](index.md) > Limitations

# Limitations

There are [configurable quotas](../concepts/limits.md) and permanent limits in Monium Traces.

**Retention limits**

Type of limit | Value
--------------- | --------
Data retention period for all spans | 4 days

**Write limits**

Type of limit | Value
--------------- | --------
Maximum size of a span batch | 4 MB
Maximum span start time in the past (`startTimeUnixNano`) | 24 hours ago
Maximum span end time in the future (`endTimeUnixNano`) | 1 hour from now
Maximum span `name` length | 2,048 characters
Maximum number of span `attributes` | 512
Maximum attribute name length | 256 characters
Maximum attribute value length | 2,097,152 characters
Maximum `events` per span | 256

**Read limits**

Type of limit | Value
--------------- | --------
Maximum number of spans displayed in the trace viewing interface | 100,000

For larger traces, split them into multiple traces and link them using [span links](https://opentelemetry.io/docs/concepts/signals/traces/#span-links).

## Incoming span validation {#validation}

Before ingestion, each batch of spans has to pass validation in terms of required fields (`trace_id`, `span_id`, timestamps), compliance with the [above limits](#traces-limits), and validity of formats. Spans that fail validation are rejected (other spans in the batch may still be accepted), and the error details go to the exporter in the response.

If some spans are missing from the UI or a trace appears incomplete, see [Incomplete traces](operations/incomplete-traces.md) for common causes and troubleshooting steps.