---
layout: default
title: Profile
nav_order: 55
---
# Profile
The Profile API provides timing information about the execution of individual components of a search request. Using the Profile API, you can debug slow requests and understand how to improve their performance. The Profile API does not measure the following:
- Network latency
- Time spent in the search fetch phase
- Amount of time a request spends in queues
- Idle time while merging shard responses on the coordinating node
The Profile API is a resource-consuming operation that adds overhead to search operations.
{: .warning}
#### Example request
To use the Profile API, include the `profile` parameter set to `true` in the search request sent to the `_search` endpoint:
```json
GET /testindex/_search
{
"profile": true,
"query" : {
"match" : { "title" : "wind" }
}
}
```
{% include copy-curl.html %}
To turn on human-readable format, include the `?human=true` query parameter in the request:
```json
GET /testindex/_search?human=true
{
"profile": true,
"query" : {
"match" : { "title" : "wind" }
}
}
```
{% include copy-curl.html %}
The response contains an additional `time` field with human-readable units, for example:
```json
"collector": [
{
"name": "SimpleTopScoreDocCollector",
"reason": "search_top_hits",
"time": "113.7micros",
"time_in_nanos": 113711
}
]
```
The Profile API response is verbose, so if you're running the request through the `curl` command, include the `?pretty` query parameter to make the response easier to understand.
{: .tip}
#### Example response
The response contains profiling information:
Response
{: .text-delta}
```json
{
"took": 21,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 2,
"relation": "eq"
},
"max_score": 0.19363807,
"hits": [
{
"_index": "testindex",
"_id": "1",
"_score": 0.19363807,
"_source": {
"title": "The wind rises"
}
},
{
"_index": "testindex",
"_id": "2",
"_score": 0.17225474,
"_source": {
"title": "Gone with the wind",
"description": "A 1939 American epic historical film"
}
}
]
},
"profile": {
"shards": [
{
"id": "[LidyZ1HVS-u93-73Z49dQg][testindex][0]",
"inbound_network_time_in_millis": 0,
"outbound_network_time_in_millis": 0,
"searches": [
{
"query": [
{
"type": "BooleanQuery",
"description": "title:wind title:rise",
"time_in_nanos": 2473919,
"breakdown": {
"set_min_competitive_score_count": 0,
"match_count": 0,
"shallow_advance_count": 0,
"set_min_competitive_score": 0,
"next_doc": 5209,
"match": 0,
"next_doc_count": 2,
"score_count": 2,
"compute_max_score_count": 0,
"compute_max_score": 0,
"advance": 9209,
"advance_count": 2,
"score": 20751,
"build_scorer_count": 4,
"create_weight": 1404458,
"shallow_advance": 0,
"create_weight_count": 1,
"build_scorer": 1034292
},
"children": [
{
"type": "TermQuery",
"description": "title:wind",
"time_in_nanos": 813581,
"breakdown": {
"set_min_competitive_score_count": 0,
"match_count": 0,
"shallow_advance_count": 0,
"set_min_competitive_score": 0,
"next_doc": 3291,
"match": 0,
"next_doc_count": 2,
"score_count": 2,
"compute_max_score_count": 0,
"compute_max_score": 0,
"advance": 7208,
"advance_count": 2,
"score": 18666,
"build_scorer_count": 6,
"create_weight": 616375,
"shallow_advance": 0,
"create_weight_count": 1,
"build_scorer": 168041
}
},
{
"type": "TermQuery",
"description": "title:rise",
"time_in_nanos": 191083,
"breakdown": {
"set_min_competitive_score_count": 0,
"match_count": 0,
"shallow_advance_count": 0,
"set_min_competitive_score": 0,
"next_doc": 0,
"match": 0,
"next_doc_count": 0,
"score_count": 0,
"compute_max_score_count": 0,
"compute_max_score": 0,
"advance": 0,
"advance_count": 0,
"score": 0,
"build_scorer_count": 2,
"create_weight": 188625,
"shallow_advance": 0,
"create_weight_count": 1,
"build_scorer": 2458
}
}
]
}
],
"rewrite_time": 192417,
"collector": [
{
"name": "SimpleTopScoreDocCollector",
"reason": "search_top_hits",
"time_in_nanos": 77291
}
]
}
],
"aggregations": []
}
]
}
}
```
## Response fields
The response includes the following fields.
Field | Data type | Description
:--- | :--- | :---
`profile` | Object | Contains profiling information.
`profile.shards` | Array of objects | A search request can be executed against one or more shards in the index, and a search may involve one or more indexes. Thus, the `profile.shards` array contains profiling information for each shard that was involved in the search.
`profile.shards.id` | String | The shard ID of the shard in the `[node-ID][index-name][shard-ID]` format.
`profile.shards.searches` | Array of objects | A search represents a query executed against the underlying Lucene index. Most search requests execute a single search against a Lucene index, but some search requests can execute more than one search. For example, including a global aggregation results in a secondary `match_all` query for the global context. The `profile.shards` array contains profiling information about each search execution.
[`profile.shards.searches.query`](#the-query-object) | Array of objects | Profiling information about the query execution.
`profile.shards.searches.rewrite_time` | Integer | All Lucene queries are rewritten. A query and its children may be rewritten more than once, until the query stops changing. The rewriting process involves performing optimizations, such as removing redundant clauses or replacing a query path with a more efficient one. After the rewriting process, the original query may change significantly. The `rewrite_time` field contains the cumulative total rewrite time for the query and all its children, in nanoseconds.
[`profile.shards.searches.collector`](#the-collector-array) | Array of objects | Profiling information about the Lucene collectors that ran the search.
[`profile.shards.aggregations`](#aggregations) | Array of objects | Profiling information about the aggregation execution.
### The `query` object
The `query` object contains the following fields.
Field | Data type | Description
:--- | :--- | :---
`type` | String | The Lucene query type into which the search query was rewritten. Corresponds to the Lucene class name (which often has the same name in OpenSearch).
`description` | String | Contains a Lucene explanation of the query. Helps differentiate queries with the same type.
`time_in_nanos` | Long | The amount of time the query took to execute, in nanoseconds. In a parent query, the time is inclusive of the execution times of all the child queries.
[`breakdown`](#the-breakdown-object) | Object | Contains timing statistics about low-level Lucene execution.
`children` | Array of objects | If a query has subqueries (children), this field contains information about the subqueries.
### The `breakdown` object
The `breakdown` object represents the timing statistics about low-level Lucene execution, broken down by method. Timings are listed in wall-clock nanoseconds and are not normalized. The `breakdown` timings are inclusive of all child times. The `breakdown` object comprises the following fields. All fields contain integer values.
Field | Description
:--- | :---
`create_weight` | A `Query` object in Lucene is immutable. Yet, Lucene should be able to reuse `Query` objects in multiple `IndexSearcher` objects. Thus, `Query` objects need to keep temporary state and statistics associated with the index in which the query is executed. To achieve reuse, every `Query` object generates a `Weight` object, which keeps the temporary context (state) associated with the `` tuple. The `create_weight` field contains the amount of time spent creating the `Weight` object.
`build_scorer` | A `Scorer` iterates over matching documents and generates a score for each document. The `build_scorer` field contains the amount of time spent generating the `Scorer` object. This does not include the time spent scoring the documents. The `Scorer` initialization time depends on the optimization and complexity of a particular query. The `build_scorer` parameter also includes the amount of time associated with caching, if caching is applicable and enabled for the query.
`next_doc` | The `next_doc` Lucene method returns the document ID of the next document that matches the query. This method is a special type of the `advance` method and is equivalent to `advance(docId() + 1)`. The `next_doc` method is more convenient for many Lucene queries. The `next_doc` field contains the amount of time required to determine the next matching document, which varies depending on the query type.
`advance` | The `advance` method is a lower-level version of the `next_doc` method in Lucene. It also finds the next matching document but necessitates that the calling query perform additional tasks, such as identifying skips. Some queries, such as conjunctions (`must` clauses in Boolean queries), cannot use `next_doc`. For those queries, `advance` is timed.
`match` | For some queries, document matching is performed in two steps. First, the document is matched approximately. Second, those documents that are approximately matched are examined through a more comprehensive process. For example, a phrase query first checks whether a document contains all terms in the phrase. Next, it verifies that the terms are in order (which is a more expensive process). The `match` field is non-zero only for those queries that use the two-step verification process.
`score` | Contains the time taken for a `Scorer` to score a particular document.
`shallow_advance` | Contains the amount of time required to execute the `advanceShallow` Lucene method.
`compute_max_score` | Contains the amount of time required to execute the `getMaxScore` Lucene method.
`set_min_competitive_score` | Contains the amount of time required to execute the `setMinCompetitiveScore` Lucene method.
`_count` | Contains the number of invocations of a ``. For example, `advance_count` contains the number of invocations of the `advance` method. Different invocations of the same method occur because the method is called on different documents. You can determine the selectivity of a query by comparing counts in different query components.
### The `collector` array
The `collector` array contains information about Lucene Collectors. A Collector is responsible for coordinating document traversal and scoring and collecting matching documents. Using Collectors, individual queries can record aggregation results and execute global queries or post-query filters.
Field | Description
:--- | :---
`name` | The collector name. In the [example response](#example-response), the `collector` is a single `SimpleTopScoreDocCollector`---the default scoring and sorting collector.
`reason` | Contains a description of the collector. For possible field values, see [Collector reasons](#collector-reasons).
`time_in_nanos` | A wall-clock time, including timing for all children.
`children` | If a collector has subcollectors (children), this field contains information about the subcollectors.
Collector times are calculated, combined, and normalized independently, so they are independent of query times.
{: .note}
#### Collector reasons
The following table describes all available collector reasons.
Reason | Description
:--- | :---
`search_sorted` | A collector that scores and sorts documents. Present in most simple searches.
`search_count` | A collector that counts the number of matching documents but does not fetch the source. Present when `size: 0` is specified.
`search_terminate_after_count` | A collector that searches for matching documents and terminates the search when it finds a specified number of documents. Present when the `terminate_after_count` query parameter is specified.
`search_min_score` | A collector that returns matching documents that have a score greater than a minimum score. Present when the `min_score` parameter is specified.
`search_multi` | A wrapper collector for other collectors. Present when search, aggregations, global aggregations, and post filters are combined in a single search.
`search_timeout` | A collector that stops running after a specified period of time. Present when a `timeout` parameter is specified.
`aggregation` | A collector for aggregations that is run against the specified query scope. OpenSearch uses a single `aggregation` collector to collect documents for all aggregations.
`global_aggregation` | A collector that is run against the global query scope. Global scope is different from a specified query scope, so in order to collect the entire dataset, a `match_all` query must be run.
## Aggregations
To profile aggregations, send an aggregation request and provide the `profile` parameter set to `true`.
#### Example request: Global aggregation
```json
GET /opensearch_dashboards_sample_data_ecommerce/_search
{
"profile": "true",
"size": 0,
"query": {
"match": { "manufacturer": "Elitelligence" }
},
"aggs": {
"all_products": {
"global": {},
"aggs": {
"avg_price": { "avg": { "field": "taxful_total_price" } }
}
},
"elitelligence_products": { "avg": { "field": "taxful_total_price" } }
}
}
```
{% include copy-curl.html %}
#### Example response: Global aggregation
The response contains profiling information:
Response
{: .text-delta}
```json
{
"took": 10,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 1370,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"all_products": {
"doc_count": 4675,
"avg_price": {
"value": 75.05542864304813
}
},
"elitelligence_products": {
"value": 68.4430200729927
}
},
"profile": {
"shards": [
{
"id": "[LidyZ1HVS-u93-73Z49dQg][opensearch_dashboards_sample_data_ecommerce][0]",
"inbound_network_time_in_millis": 0,
"outbound_network_time_in_millis": 0,
"searches": [
{
"query": [
{
"type": "ConstantScoreQuery",
"description": "ConstantScore(manufacturer:elitelligence)",
"time_in_nanos": 1367487,
"breakdown": {
"set_min_competitive_score_count": 0,
"match_count": 0,
"shallow_advance_count": 0,
"set_min_competitive_score": 0,
"next_doc": 634321,
"match": 0,
"next_doc_count": 1370,
"score_count": 0,
"compute_max_score_count": 0,
"compute_max_score": 0,
"advance": 173250,
"advance_count": 2,
"score": 0,
"build_scorer_count": 4,
"create_weight": 132458,
"shallow_advance": 0,
"create_weight_count": 1,
"build_scorer": 427458
},
"children": [
{
"type": "TermQuery",
"description": "manufacturer:elitelligence",
"time_in_nanos": 1174794,
"breakdown": {
"set_min_competitive_score_count": 0,
"match_count": 0,
"shallow_advance_count": 0,
"set_min_competitive_score": 0,
"next_doc": 470918,
"match": 0,
"next_doc_count": 1370,
"score_count": 0,
"compute_max_score_count": 0,
"compute_max_score": 0,
"advance": 172084,
"advance_count": 2,
"score": 0,
"build_scorer_count": 4,
"create_weight": 114041,
"shallow_advance": 0,
"create_weight_count": 1,
"build_scorer": 417751
}
}
]
}
],
"rewrite_time": 42542,
"collector": [
{
"name": "MultiCollector",
"reason": "search_multi",
"time_in_nanos": 778406,
"children": [
{
"name": "EarlyTerminatingCollector",
"reason": "search_count",
"time_in_nanos": 70290
},
{
"name": "ProfilingAggregator: [elitelligence_products]",
"reason": "aggregation",
"time_in_nanos": 502780
}
]
}
]
},
{
"query": [
{
"type": "ConstantScoreQuery",
"description": "ConstantScore(*:*)",
"time_in_nanos": 995345,
"breakdown": {
"set_min_competitive_score_count": 0,
"match_count": 0,
"shallow_advance_count": 0,
"set_min_competitive_score": 0,
"next_doc": 930803,
"match": 0,
"next_doc_count": 4675,
"score_count": 0,
"compute_max_score_count": 0,
"compute_max_score": 0,
"advance": 2209,
"advance_count": 2,
"score": 0,
"build_scorer_count": 4,
"create_weight": 23875,
"shallow_advance": 0,
"create_weight_count": 1,
"build_scorer": 38458
},
"children": [
{
"type": "MatchAllDocsQuery",
"description": "*:*",
"time_in_nanos": 431375,
"breakdown": {
"set_min_competitive_score_count": 0,
"match_count": 0,
"shallow_advance_count": 0,
"set_min_competitive_score": 0,
"next_doc": 389875,
"match": 0,
"next_doc_count": 4675,
"score_count": 0,
"compute_max_score_count": 0,
"compute_max_score": 0,
"advance": 1167,
"advance_count": 2,
"score": 0,
"build_scorer_count": 4,
"create_weight": 9458,
"shallow_advance": 0,
"create_weight_count": 1,
"build_scorer": 30875
}
}
]
}
],
"rewrite_time": 8792,
"collector": [
{
"name": "ProfilingAggregator: [all_products]",
"reason": "aggregation_global",
"time_in_nanos": 1310536
}
]
}
],
"aggregations": [
{
"type": "AvgAggregator",
"description": "elitelligence_products",
"time_in_nanos": 319918,
"breakdown": {
"reduce": 0,
"post_collection_count": 1,
"build_leaf_collector": 130709,
"build_aggregation": 2709,
"build_aggregation_count": 1,
"build_leaf_collector_count": 2,
"post_collection": 584,
"initialize": 4750,
"initialize_count": 1,
"reduce_count": 0,
"collect": 181166,
"collect_count": 1370
}
},
{
"type": "GlobalAggregator",
"description": "all_products",
"time_in_nanos": 1519340,
"breakdown": {
"reduce": 0,
"post_collection_count": 1,
"build_leaf_collector": 134625,
"build_aggregation": 59291,
"build_aggregation_count": 1,
"build_leaf_collector_count": 2,
"post_collection": 5041,
"initialize": 24500,
"initialize_count": 1,
"reduce_count": 0,
"collect": 1295883,
"collect_count": 4675
},
"children": [
{
"type": "AvgAggregator",
"description": "avg_price",
"time_in_nanos": 775967,
"breakdown": {
"reduce": 0,
"post_collection_count": 1,
"build_leaf_collector": 98999,
"build_aggregation": 33083,
"build_aggregation_count": 1,
"build_leaf_collector_count": 2,
"post_collection": 2209,
"initialize": 1708,
"initialize_count": 1,
"reduce_count": 0,
"collect": 639968,
"collect_count": 4675
}
}
]
}
]
}
]
}
}
```
#### Example request: Non-global aggregation
```json
GET /opensearch_dashboards_sample_data_ecommerce/_search
{
"size": 0,
"aggs": {
"avg_taxful_total_price": {
"avg": {
"field": "taxful_total_price"
}
}
}
}
```
{% include copy-curl.html %}
#### Example response: Non-global aggregation
The response contains profiling information:
Response
{: .text-delta}
```json
{
"took": 13,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": {
"value": 4675,
"relation": "eq"
},
"max_score": null,
"hits": []
},
"aggregations": {
"avg_taxful_total_price": {
"value": 75.05542864304813
}
},
"profile": {
"shards": [
{
"id": "[LidyZ1HVS-u93-73Z49dQg][opensearch_dashboards_sample_data_ecommerce][0]",
"inbound_network_time_in_millis": 0,
"outbound_network_time_in_millis": 0,
"searches": [
{
"query": [
{
"type": "ConstantScoreQuery",
"description": "ConstantScore(*:*)",
"time_in_nanos": 1690820,
"breakdown": {
"set_min_competitive_score_count": 0,
"match_count": 0,
"shallow_advance_count": 0,
"set_min_competitive_score": 0,
"next_doc": 1614112,
"match": 0,
"next_doc_count": 4675,
"score_count": 0,
"compute_max_score_count": 0,
"compute_max_score": 0,
"advance": 2708,
"advance_count": 2,
"score": 0,
"build_scorer_count": 4,
"create_weight": 20250,
"shallow_advance": 0,
"create_weight_count": 1,
"build_scorer": 53750
},
"children": [
{
"type": "MatchAllDocsQuery",
"description": "*:*",
"time_in_nanos": 770902,
"breakdown": {
"set_min_competitive_score_count": 0,
"match_count": 0,
"shallow_advance_count": 0,
"set_min_competitive_score": 0,
"next_doc": 721943,
"match": 0,
"next_doc_count": 4675,
"score_count": 0,
"compute_max_score_count": 0,
"compute_max_score": 0,
"advance": 1042,
"advance_count": 2,
"score": 0,
"build_scorer_count": 4,
"create_weight": 5041,
"shallow_advance": 0,
"create_weight_count": 1,
"build_scorer": 42876
}
}
]
}
],
"rewrite_time": 22000,
"collector": [
{
"name": "MultiCollector",
"reason": "search_multi",
"time_in_nanos": 3672676,
"children": [
{
"name": "EarlyTerminatingCollector",
"reason": "search_count",
"time_in_nanos": 78626
},
{
"name": "ProfilingAggregator: [avg_taxful_total_price]",
"reason": "aggregation",
"time_in_nanos": 2834566
}
]
}
]
}
],
"aggregations": [
{
"type": "AvgAggregator",
"description": "avg_taxful_total_price",
"time_in_nanos": 1973702,
"breakdown": {
"reduce": 0,
"post_collection_count": 1,
"build_leaf_collector": 199292,
"build_aggregation": 13584,
"build_aggregation_count": 1,
"build_leaf_collector_count": 2,
"post_collection": 6125,
"initialize": 6916,
"initialize_count": 1,
"reduce_count": 0,
"collect": 1747785,
"collect_count": 4675
}
}
]
}
]
}
}
```
### Response fields
The `aggregations` array contains aggregation objects with the following fields.
Field | Data type | Description
:--- | :--- | :---
`type` | String | The aggregator type. In the [non-global aggregation example response](#example-response-non-global-aggregation), the aggregator type is `AvgAggregator`. [Global aggregation example response](#example-request-global-aggregation) contains a `GlobalAggregator` with an `AvgAggregator` child.
`description` | String | Contains a Lucene explanation of the aggregation. Helps differentiate aggregations with the same type.
`time_in_nanos` | Long | The amount of time taken to execute the aggregation, in nanoseconds. In a parent aggregation, the time is inclusive of the execution times of all the child aggregations.
[`breakdown`](#the-breakdown-object-1) | Object | Contains timing statistics about low-level Lucene execution.
`children` | Array of objects | If an aggregation has subaggregations (children), this field contains information about the subaggregations.
`debug` | Object | Some aggregations return a `debug` object that describes the details of the underlying execution.
### The `breakdown` object
The `breakdown` object represents the timing statistics about low-level Lucene execution, broken down by method. Each field in the `breakdown` object represents an internal Lucene method executed within the aggregation. Timings are listed in wall-clock nanoseconds and are not normalized. The `breakdown` timings are inclusive of all child times. The `breakdown` object is comprised of the following fields. All fields contain integer values.
Field | Description
:--- | :---
`initialize` | Contains the amount of time taken to execute the `preCollection()` callback method during `AggregationCollectorManager` creation.
`build_leaf_collector`| Contains the time spent running the `getLeafCollector()` method of the aggregation, which creates a new collector to collect the given context.
`collect`| Contains the time spent collecting the documents into buckets.
`post_collection`| Contains the time spent running the aggregation’s `postCollection()` callback method.
`build_aggregation`| Contains the time spent running the aggregation’s `buildAggregations()` method, which builds the results of this aggregation.
`reduce`| Contains the time spent in the `reduce` phase.
`_count` | Contains the number of invocations of a ``. For example, `build_leaf_collector_count` contains the number of invocations of the `build_leaf_collector` method.