Merge branch 'amandarueda-master-patch-31767' into 'master'

Added calculation of pipeline quota usage

See merge request gitlab-org/gitlab!48254

doc/ci/pipelines/index.md

@@ -261,6 +261,18 @@ The union of A, B, and C is (1, 4) and (6, 7). Therefore, the total running time
 (4 - 1) + (7 - 6) => 4
 ```
 
+#### How pipeline quota usage is calculated
+
+Pipeline quota usage is calculated as the sum of the duration of each individual job. This is slightly different to how pipeline _duration_ is [calculated](#how-pipeline-duration-is-calculated). Pipeline quota usage doesn't consider any overlap of jobs running in parallel.
+
+For example, a pipeline consists of the following jobs:
+
+- Job A takes 3 minutes.
+- Job B takes 3 minutes.
+- Job C takes 2 minutes.
+
+The pipeline quota usage is the sum of each job's duration. In this example, 8 runner minutes would be used, calculated as: 3 + 3 + 2.
+
 ### Pipeline security on protected branches
 
 A strict security model is enforced when pipelines are executed on