Adds profiler for knn query

[shatejas]

Description

Adds exact and ann timings and counts with knn query profile API

You can find sample response here: concurrent_nofilter.json concurrent.json profile_filter.json faiss_profile.json

CIs will fail since it require a change in Opensearch-core

Pending:

• Opensearch PR https://github.com/opensearch-project/OpenSearch/pull/17146
• unit tests

Related Issues

Resolves https://github.com/opensearch-project/k-NN/issues/2286

Partial response

"profile": {
		"shards": [
			{
				"id": "[6lfotEMuRUqgq0kM6BfLSQ][target_index_faiss][0]",
				"inbound_network_time_in_millis": 0,
				"outbound_network_time_in_millis": 0,
				"searches": [
					{
						"query": [
							{
								"type": "NativeEngineKnnVectorQuery",
								"description": "NativeEngineKnnVectorQuery[]...KNNQuery[]",
								"time_in_nanos": 27173585,
								"breakdown": {
									"set_min_competitive_score_count": 0,
									"exact_knn_search": 0,
									"match_count": 0,
									"shallow_advance_count": 0,
									"next_doc": 3542,
									"score_count": 3,
									"compute_max_score_count": 0,
									"advance": 0,
									"advance_count": 0,
									"score": 2459,
									"shallow_advance": 0,
									"create_weight_count": 1,
									"build_scorer": 614792,
									"ann_search": 0,
									"set_min_competitive_score": 0,
									"match": 0,
									"next_doc_count": 4,
									"compute_max_score": 0,
									"build_scorer_count": 2,
									"create_weight": 26552792,
									"ann_search_count": 0,
									"exact_knn_search_count": 0
								},
								"children": [
									{
										"type": "KNNQuery",
										"description": "",
										"time_in_nanos": 2821209,
										"breakdown": {
											"set_min_competitive_score_count": 0,
											"exact_knn_search": 0,
											"match_count": 0,
											"shallow_advance_count": 0,
											"next_doc": 0,
											"score_count": 0,
											"compute_max_score_count": 0,
											"advance": 0,
											"advance_count": 0,
											"score": 0,
											"shallow_advance": 0,
											"create_weight_count": 0,
											"build_scorer": 0,
											"ann_search": 2821209,
											"set_min_competitive_score": 0,
											"match": 0,
											"next_doc_count": 0,
											"compute_max_score": 0,
											"build_scorer_count": 0,
											"create_weight": 0,
											"ann_search_count": 1,
											"exact_knn_search_count": 0
										}
									}
								]
							}
						],
						"rewrite_time": 29292,
						"collector": [
							{
								"name": "SimpleTopScoreDocCollector",
								"reason": "search_top_hits",
								"time_in_nanos": 381916
							}
						]
					}
				],
				"aggregations": []
			}

Check List

• [x] New functionality includes testing.
• [x] Commits are signed per the DCO using --signoff.
• [ ] Public documentation issue/PR created.

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[VijayanB]

@shatejas Can you post the sample response as text in comment if it is small so that we don't have to download?

[shatejas]

@VijayanB there are multiple of them and aren't small so uploaded them. I can add partial if it helps