We are having trouble with MariaDB hanging due to a "semaphore wait". We then have to shut MariaDB down as it typically won't recover, unless it restarts itself, which happens if we wait long enough. But if its gone on long enough MariaDB won't even shutdown, it hangs indefinitely waiting for some other internal service. I don't remember the exact name and we've been fast enough I haven't seen it in a while. We've had the database on two completely different servers and still see the problem. Both servers were bought new for this project and are a year or less old. They are running all SSD drives, Debian 7 64bit with MariaDB 10.1 from the MariaDB APT repository. Since the XtraDB engine was usually mentioned in the logged messages we switched back to the Oracle InnoDB engine. Although this seems to have reduced the frequency it didn't fix it. Can anyone give some advice on fixing this. It really seams like a bug in MariaDB. I'll try to provide any needed info. TIA - Jon -- Jon Foster jon@jfpossibilities.com