Git Forensics long runtime for first build on new branches

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For each new branch / PR, the mineRepository step for the first build is taking ~10 minutes. I can only assume it’s scanning an excessive amount of the commit history. Subsequent builds for additional commits on the same branch/job take seconds at most.

Is this expected behavior, or is something not right/optimal with my setup? Can it not use a cache / data from the controller build (reference job) to only require scanning of new commits in the branch?

Project uses a GitHub sources multibranch pipeline with Jenkinsfile:

    stages {
        stage('Prepare') {
            steps {
                discoverGitReferenceBuild([
                    referenceJob: "project/master",
                    targetBranch: "master",
                    latestBuildIfNotFound: true,
                ])
                mineRepository()
                gitDiffStat()

Console output, for first build on new branch with single new commit compared to controller:

[Pipeline] discoverGitReferenceBuild
[ReferenceFinder] Configured reference job: 'project/master'
[ReferenceFinder] -> detected 200 commits in current branch (last one: '4ce6a6e')
[ReferenceFinder] -> adding 1 commits from build '#774' of reference job (last one: '7d40491')
[ReferenceFinder] -> found a matching commit in current branch and target branch: '7d40491'
[ReferenceFinder] -> found build '#774' in reference job with matching commits
[ReferenceFinder] Found reference build '#774' for target branch
[ReferenceFinder] -> Build '#774' has a result SUCCESS
[Pipeline] mineRepository
The recommended git tool is: NONE
using credential 03a37a5d-afa4-4d31-b730-b3a7c16e5b10
 > git rev-parse HEAD^{commit} # timeout=10
The recommended git tool is: NONE
using credential 03a37a5d-afa4-4d31-b730-b3a7c16e5b10
[Forensics] Creating SCM miner to obtain statistics for affected repository files
[Forensics] -> checking SCM 'git git@github.com:Org/project.git'
[Forensics] -> Git miner successfully created in working tree '/var/lib/jenkins/workspace/branch_name'
[Forensics] Analyzing the commit log of the Git repository '/var/lib/jenkins/workspace/branch_name'
[Forensics] Found 9906 commits
[Forensics] -> Created report in 643 seconds
[Forensics] -> 9636 commits with differences analyzed
[Forensics] -> 601696 MODIFY commit diff items
[Forensics] -> 15607 RENAME commit diff items
[Forensics] -> 238256 DELETE commit diff items
[Forensics] -> 41412751 lines added
[Forensics] -> 37691214 lines deleted
[Pipeline] gitDiffStat

Jenkins setup: (Single server)
Jenkins 2.492.2
Forensics API Plugin 3.1.0
Git Forensics Plugin 3.2.0