Prometheus - v2.47.0

This release adds an experimental OpenTelemetry (OTLP) Ingestion feature, and also new setting keep_dropped_targets to limit the amount of dropped targets held in memory. This defaults to 0 meaning 'no limit', so we encourage users with large Prometheus to try setting a limit such as 100.

This version is compiled with Go 1.21.0.

• [FEATURE] Web: Add OpenTelemetry (OTLP) Ingestion endpoint. #12571 #12643
• [FEATURE] Scraping: Optionally limit detail on dropped targets, to save memory. #12647
• [ENHANCEMENT] TSDB: Write head chunks to disk in the background to reduce blocking. #11818
• [ENHANCEMENT] PromQL: Speed up aggregate and function queries. #12682
• [ENHANCEMENT] PromQL: More efficient evaluation of query with timestamp(). #12579
• [ENHANCEMENT] API: Faster streaming of Labels to JSON. #12598
• [ENHANCEMENT] Agent: Memory pooling optimisation. #12651
• [ENHANCEMENT] TSDB: Prevent storage space leaks due to terminated snapshots on shutdown. #12664
• [ENHANCEMENT] Histograms: Refactoring and optimisations. #12352 #12584 #12596 #12711 #12054
• [ENHANCEMENT] Histograms: Add histogram_stdvar and histogram_stddev functions. #12614
• [ENHANCEMENT] Remote-write: add http.resend_count tracing attribute. #12676
• [ENHANCEMENT] TSDB: Support native histograms in snapshot on shutdown. #12722
• [BUGFIX] TSDB/Agent: ensure that new series get written to WAL on rollback. #12592
• [BUGFIX] Scraping: fix infinite loop on exemplar in protobuf format. #12737