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

# Blocked Sessions, Microsoft SQL Server KPI card, Vortex IQ Nerve Centre

> sys.dm_exec_requests where blocking_session_id != 0. Long blocking chains stall the app.

**[Nerve Centre KPIs](/nerve-centre/kpi-cards/mssql) · [Audit Profile](/nerve-centre/kpi-cards/mssql/audit) · [Sentiment Settings](/nerve-centre/kpi-cards/mssql/sentiment)**

## At a glance

* **Category:** Concurrency
* **Type:** Key Metrics
* **Chart:** kpi
* **Format:** number
* **Time window:** RT
* **Alert trigger:** >0 blocked >30s

## Calculation

sys.dm\_exec\_requests where blocking\_session\_id != 0. Long blocking chains stall the app.

## Known limitations

*Known limitations, FAQs, or reconciliation notes specific to this card. Replace this block when authored.*