Prometheus v3.13.0

A substantial Long Term Support (LTS) release focusing on security hardening, query performance optimization, and refined controls for Native Histograms. Key highlights include memory reduction in the TSDB, new metadata search APIs, and enhanced per-query statistics to help users debug performance bottlenecks.

Improved Security for UI and HTTP Client Redirects — This is a critical update for compliance-minded users, addressing vulnerabilities related to cross-site scripting in the UI and potential credential leakage when HTTP clients follow redirects to external hosts.

Significant TSDB Performance and Memory Optimizations — SREs and operators will see reduced infrastructure costs and faster dashboards. Technical improvements in chunk population and histogram decoding reduce memory allocations by up to 50% and speed up queries by roughly 15%.

Enhanced Per-Query Execution Statistics and Metrics — Provides much-needed visibility into query efficiency. By distinguishing between storage I/O (samples read) and calculation-heavy samples, users can better tune expensive queries and troubleshoot resource exhaustion.

Flexible Per-Target Histogram Scrape Overrides — Gives operators more granular control over histogram ingestion. You can now use relabeling rules to decide on a per-target basis whether to scrape or convert classic histograms to native ones.

New Experimental Search Endpoints for Metric Metadata — Users searching through massive metric namespaces can now use experimental endpoints to quickly discover metric names, labels, and values via the API.