* [FEATURE] **experimental** TSDB: Snapshot in-memory chunks on shutdown for faster restarts. Behind `--enable-feature=memory-snapshot-on-shutdown` flag. #7229
* [FEATURE] **experimental** Scrape: Configure scrape interval and scrape timeout via relabeling using `__scrape_interval__` and `__scrape_timeout__` labels respectively. #8911
* [FEATURE] Scrape: Add `scrape_timeout_seconds` and `scrape_sample_limit` metric. Behind `--enable-feature=extra-scrape-metrics` flag to avoid additional cardinality by default. #9247#9295
* [ENHANCEMENT] Scrape: Add `--scrape.timestamp-tolerance` flag to adjust scrape timestamp tolerance when enabled via `--scrape.adjust-timestamps`. #9283
* [ENHANCEMENT] Remote Write: Improve throughput when sending exemplars. #8921
* [ENHANCEMENT] TSDB: Optimise WAL loading by removing extra map and caching min-time #9160
* [ENHANCEMENT] promtool: Speed up checking for duplicate rules. #9262/#9306
* [ENHANCEMENT] Scrape: Reduce allocations when parsing the metrics. #9299
* [ENHANCEMENT] docker_sd: Support host network mode #9125
* [BUGFIX] Exemplars: Fix panic when resizing exemplar storage from 0 to a non-zero size. #9286
* [BUGFIX] TSDB: Correctly decrement `prometheus_tsdb_head_active_appenders` when the append has no samples. #9230
* [BUGFIX] promtool rules backfill: Return 1 if backfill was unsuccessful. #9303
* [BUGFIX] config: Fix a panic when reloading configuration with a `null` relabel action. #9224
## 2.29.2 / 2021-08-27
* [BUGFIX] Fix Kubernetes SD failing to discover Ingress in Kubernetes v1.22. #9205