Explanation with a comment

Author: danielmarbach

src/Particular.LicensingComponent/WebApi/LicensingController.cs

@@ -68,6 +68,9 @@ public async Task GetThroughputReportFile([FromQuery(Name = "spVersion")] string
                 FileName = $"{fileName}.zip"
             }.ToString();
 
+            // The zip archive is written directly to the response body stream and has to remain open until the response is fully sent.
+            // This is done for performance reasons to avoid buffering the entire report in memory before sending it.
+            // The BodyWriter is used as a stream to avoid into synchronous IO operations that would be prevented by the ASP.NET Core pipeline.
             using var archive = new ZipArchive(Response.BodyWriter.AsStream(), ZipArchiveMode.Create, leaveOpen: true);
             var entry = archive.CreateEntry($"{fileName}.json");
             await using var entryStream = entry.Open();