Describe the bug

I imported my Pocket library, totaling 27k+ links, and have been archiving those links on and off for a week. I went away for a few days, and figured I'd let the process run on my server. When I returned, I found the RAM completely maxed out on the box (16GBs) and dozens of stray Chromium processes still running. ArchiveBox was run in Docker, so I was able to kill the container and reclaim the RAM, rather than needing to kill all of the processes.

My theory is that the timeout doesn't kill the underlying process properly and so it just stayed open, but I'm not 100% sure.

Steps to reproduce

1. Create large ArchiveBox db.
2. Set low timeout for archving.
3. Run archivebox update.
4. Wait a while.
5. Watch for stray Chromium processes.

Screenshots or log output

I can pull some logs if needed.

Software versions

• OS: Ubuntu
• ArchiveBox version: archivebox/archivebox:latest
• Python version: 3.8 (whatever's in the Dockerfile)
• Chrome version: Not sure (same as above, whatever's in the Dockerfile)