> ## 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.

# Query Latency p50 (ms), kpi

> Query Latency p50 (ms) for PostgreSQL instances. Tracked live in Vortex IQ Nerve Centre. How to read it, why it matters, and how to act on it.

**Card class:** [Non-Hero](/nerve-centre/overview#card-classes-explained)  •  **Category:** [Performance](/nerve-centre/connectors#connectors-by-type)

## At a glance

> **Query Latency p50 (ms)** is the median query execution time: half of all statements finished faster than this number, half slower. It is the "typical query" view, the experience the average request gets. Read it next to the p95 and p99 cards: when p50 holds steady but the upper percentiles climb, the problem is a slow subset, not a broad slowdown.

## What it tracks

The card reports the 50th-percentile (median) execution time across statements in the window, refreshed in real time and smoothed over a rolling five-minute window (`RT/5m`). It is computed from per-statement timing in `pg_stat_statements` (the call-weighted `mean_exec_time` distribution), or from log-derived durations where `log_min_duration_statement` is enabled. Like the other latency cards it measures server-side execution time only: it excludes time a statement spends waiting for a connection slot and excludes network round-trip. The median is deliberately resistant to outliers, so a single pathological query barely moves it, which is exactly why p50 answers "how fast is a normal query" while the p95 and p99 cards answer "how bad is the tail". There is no alert on this card; the actionable latency thresholds live on [Query Latency p95 (ms)](/nerve-centre/kpi-cards/postgresql/query-latency-p95-ms) (alerts above 200ms) and [Query Latency p99 (ms)](/nerve-centre/kpi-cards/postgresql/query-latency-p99-ms) (alerts above 500ms).

## Reconciling against the source

Reproduce the basis in PostgreSQL with `SELECT query, calls, mean_exec_time FROM pg_stat_statements ORDER BY calls DESC;` (requires the `pg_stat_statements` extension), or read exact durations by setting `log_min_duration_statement` low and reading the logged statement times. On a managed service, compare against AWS RDS Performance Insights, Google Cloud SQL Query Insights, or Azure Database for PostgreSQL Query Store, noting that those consoles often headline *average* latency, which sits below the median on a tailed workload.

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### Tracked live in Vortex IQ Nerve Centre

*Query Latency p50 (ms)* is one of hundreds of KPI pulses Vortex IQ tracks across PostgreSQL and 70+ other ecommerce connectors. Nerve Centre runs the detection layer; Vortex Mind investigates the cause when something moves; Ask Viq lets you interrogate any number in plain English.

[Start for free](https://app.vortexiq.ai/login) or [book a demo](https://www.vortexiq.ai/contact-us) to see this metric running on your own data.