The downloads in OPS (and other applications) work with scheduled tasks which run once a day. Meaning that if you download a preprint today, it will show up in the download stats with a delay of 1-24 hours depending on when the scheduled task is run.
The data is first saved to actual log files in “files/usageStats” folder in OPS. When you download a preprint, you should see a corresponding line in files/usageStats/usageEventLogs". The “usageEventLogs” subfolder is the folder where the current log file lives in. When the day is over the system will start a new log file and the old one is processed with the task and moved to the “archive” folder.
Let me know if you are not seeing any log files or lines in the files.
The statistics framework that processes the logs needs to do a bunch of things for COUNTER (which are generally a good idea for reliable numbers) like debouncing, bot removal, etc. but which are not suitable for instant feedback. If you’re looking for numbers that reflect changes instantly, tools like Google Analytics etc. might be better.
Public Knowledge Project Team