Add RW2 support

CHANGELOG.md

@@ -9,6 +9,7 @@
 * [CHANGE] Distributor: removed the `cortex_distributor_label_values_with_newlines_total` metric. #10977
 * [CHANGE] Ingester/Distributor: renamed the experimental `max_cost_attribution_cardinality_per_user` config to `max_cost_attribution_cardinality`. #11092
 * [CHANGE] Frontend: The subquery spin-off feature is now enabled with `-query-frontend.subquery-spin-off-enabled=true` instead of `-query-frontend.instant-queries-with-subquery-spin-off=.*` #11153
+* [FEATURE] Distributor: experimental support for Prometheus Remote Write 2.0 protocol. Limitations: created timestamp is ignored, native histograms with custom buckets are rejected, per series metadata is merged on metric family level automatically, ingestion might fail if client sends ProtoBuf fields out of order. #11100 #11101
 * [ENHANCEMENT] Ingester: Add support for exporting native histogram cost attribution metrics (`cortex_ingester_attributed_active_native_histogram_series` and `cortex_ingester_attributed_active_native_histogram_buckets`) with labels specified by customers to a custom Prometheus registry. #10892
 * [ENHANCEMENT] Store-gateway: Download sparse headers uploaded by compactors. Compactors have to be configured with `-compactor.upload-sparse-index-headers=true` option. #10879 #11072.
 * [ENHANCEMENT] Compactor: Upload block index file and multiple segment files concurrently. Concurrency scales linearly with block size up to `-compactor.max-per-block-upload-concurrency`. #10947