Commit and stage execution time not constant

I am currently using LibGit2Sharp (v0.15.0) to keep track of differences in many HTML files (~10,000). Each change to a file or new file results in a single commit. I have noticed that writes and commits are getting slower and slower. Here is a visualization of my tests:

I tried to adjust the repository.Stage(...) and repository.Commit(...) time so that the size of the HTML file size was not taken into account. This was done by simply dividing the write and commit time by the file size.

I was not sure whether this slow down was expected, but after a bit of reading around, it seems to me that git commit should be constant time with respect to the number of commits or files already in the repository. I am not sure if the same assumption can be made about staging.

Is this a known issue with LibGit2Sharp? Or libgit2?

Reproduziere die gemeldete Verlangsamung mit LibGit2Sharp v0.15.0 unter Verwendung der Arbeitslast des Issues von etwa 10.000 HTML-Dateien und messe Stage und Commit, während das Repository wächst. Vergleiche die Ergebnisse mit dem erwarteten Git-Verhalten und bestimme, ob die Ursache bei LibGit2Sharp oder libgit2 liegt; dokumentiere die Erkenntnis und jedes relevante Upstream-Issue.