Remove benchmarks folder from k-NN repo

CHANGELOG.md

@@ -24,4 +24,5 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 ### Infrastructure
 ### Documentation
 ### Maintenance
+* Remove benchmarks folder from k-NN repo [#2127](https://github.com/opensearch-project/k-NN/pull/2127)
 ### Refactoring

benchmarks/README.md

@@ -0,0 +1,4 @@
+## Benchmark Folder Tools Deprecated
+All benchmark workloads have been moved to [OpenSearch Benchmark Workloads](https://github.com/opensearch-project/opensearch-benchmark-workloads/tree/main/vectorsearch). Please use OSB tool to run the benchmarks.
+
+If you are still interested in using the old tool, the benchmarks are moved to the [branch](https://github.com/opensearch-project/k-NN/tree/old-benchmarks/benchmarks).