Bucket correlation aggregation
editBucket correlation aggregation
editThis functionality is in technical preview and may be changed or removed in a future release. Elastic will work to fix any issues, but features in technical preview are not subject to the support SLA of official GA features.
A sibling pipeline aggregation which executes a correlation function on the configured sibling multi-bucket aggregation.
Parameters
edit-
buckets_path
-
(Required, string)
Path to the buckets that contain one set of values to correlate.
For syntax, see
buckets_path
Syntax. -
function
-
(Required, object) The correlation function to execute.
Properties of
function
-
count_correlation
-
(Required*, object) The configuration to calculate a count correlation. This function is designed for determining the correlation of a term value and a given metric. Consequently, it needs to meet the following requirements.
-
The
buckets_path
must point to a_count
metric. -
The total count of all the
bucket_path
count values must be less than or equal toindicator.doc_count
. -
When utilizing this function, an initial calculation to gather the required
indicator
values is required.
Properties of
count_correlation
-
indicator
-
(Required, object) The indicator with which to correlate the configured
bucket_path
values.Properties of
indicator
-
doc_count
-
(Required, integer)
The total number of documents that initially created the
expectations
. It’s required to be greater than or equal to the sum of all values in thebuckets_path
as this is the originating superset of data to which the term values are correlated. -
expectations
-
(Required, array)
An array of numbers with which to correlate the configured
bucket_path
values. The length of this value must always equal the number of buckets returned by thebucket_path
. -
fractions
-
(Optional, array)
An array of fractions to use when averaging and calculating variance. This should be used if the pre-calculated data and the
buckets_path
have known gaps. The length offractions
, if provided, must equalexpectations
.
-
-
The
-
Syntax
editA bucket_correlation
aggregation looks like this in isolation:
Example
editThe following snippet correlates the individual terms in the field version
with the latency
metric. Not shown
is the pre-calculation of the latency
indicator values, which was done utilizing the
percentiles aggregation.
This example is only using the 10s percentiles.
POST correlate_latency/_search?size=0&filter_path=aggregations { "aggs": { "buckets": { "terms": { "field": "version", "size": 2 }, "aggs": { "latency_ranges": { "range": { "field": "latency", "ranges": [ { "to": 0.0 }, { "from": 0, "to": 105 }, { "from": 105, "to": 225 }, { "from": 225, "to": 445 }, { "from": 445, "to": 665 }, { "from": 665, "to": 885 }, { "from": 885, "to": 1115 }, { "from": 1115, "to": 1335 }, { "from": 1335, "to": 1555 }, { "from": 1555, "to": 1775 }, { "from": 1775 } ] } }, "bucket_correlation": { "bucket_correlation": { "buckets_path": "latency_ranges>_count", "function": { "count_correlation": { "indicator": { "expectations": [0, 52.5, 165, 335, 555, 775, 1000, 1225, 1445, 1665, 1775], "doc_count": 200 } } } } } } } } }
The term buckets containing a range aggregation and the bucket correlation aggregation. Both are utilized to calculate the correlation of the term values with the latency. |
|
The range aggregation on the latency field. The ranges were created referencing the percentiles of the latency field. |
|
The bucket correlation aggregation that calculates the correlation of the number of term values within each range and the previously calculated indicator values. |
And the following may be the response:
{ "aggregations" : { "buckets" : { "doc_count_error_upper_bound" : 0, "sum_other_doc_count" : 0, "buckets" : [ { "key" : "1.0", "doc_count" : 100, "latency_ranges" : { "buckets" : [ { "key" : "*-0.0", "to" : 0.0, "doc_count" : 0 }, { "key" : "0.0-105.0", "from" : 0.0, "to" : 105.0, "doc_count" : 1 }, { "key" : "105.0-225.0", "from" : 105.0, "to" : 225.0, "doc_count" : 9 }, { "key" : "225.0-445.0", "from" : 225.0, "to" : 445.0, "doc_count" : 0 }, { "key" : "445.0-665.0", "from" : 445.0, "to" : 665.0, "doc_count" : 0 }, { "key" : "665.0-885.0", "from" : 665.0, "to" : 885.0, "doc_count" : 0 }, { "key" : "885.0-1115.0", "from" : 885.0, "to" : 1115.0, "doc_count" : 10 }, { "key" : "1115.0-1335.0", "from" : 1115.0, "to" : 1335.0, "doc_count" : 20 }, { "key" : "1335.0-1555.0", "from" : 1335.0, "to" : 1555.0, "doc_count" : 20 }, { "key" : "1555.0-1775.0", "from" : 1555.0, "to" : 1775.0, "doc_count" : 20 }, { "key" : "1775.0-*", "from" : 1775.0, "doc_count" : 20 } ] }, "bucket_correlation" : { "value" : 0.8402398981360937 } }, { "key" : "2.0", "doc_count" : 100, "latency_ranges" : { "buckets" : [ { "key" : "*-0.0", "to" : 0.0, "doc_count" : 0 }, { "key" : "0.0-105.0", "from" : 0.0, "to" : 105.0, "doc_count" : 19 }, { "key" : "105.0-225.0", "from" : 105.0, "to" : 225.0, "doc_count" : 11 }, { "key" : "225.0-445.0", "from" : 225.0, "to" : 445.0, "doc_count" : 20 }, { "key" : "445.0-665.0", "from" : 445.0, "to" : 665.0, "doc_count" : 20 }, { "key" : "665.0-885.0", "from" : 665.0, "to" : 885.0, "doc_count" : 20 }, { "key" : "885.0-1115.0", "from" : 885.0, "to" : 1115.0, "doc_count" : 10 }, { "key" : "1115.0-1335.0", "from" : 1115.0, "to" : 1335.0, "doc_count" : 0 }, { "key" : "1335.0-1555.0", "from" : 1335.0, "to" : 1555.0, "doc_count" : 0 }, { "key" : "1555.0-1775.0", "from" : 1555.0, "to" : 1775.0, "doc_count" : 0 }, { "key" : "1775.0-*", "from" : 1775.0, "doc_count" : 0 } ] }, "bucket_correlation" : { "value" : -0.5759855613334943 } } ] } } }