mysql keeping running but stops serving

[David Banning]

After years of great service mysql stops working every 24 hours or so.
Consulting the error log 3s1.com.err (my domain is 3s1.com) 

The log shows the server starting,  then without logging anything, it stops
working after maybe 18 hours - it keeps running, but stops serving. 

The shutdown is my command, but you can see mysql does not want to shutdown.
The "Forcing close of thead.." continues indefinitely.

Any pointers toward resolution would be helpful. Can I get more elaborate 
logging?



150422 22:59:17  mysqld started
150422 22:59:17 [Warning] No argument was provided to --log-bin, and --log-bin-index was not used; so replication may break when this MySQL server acts as a master and has his hostname changed!! Please use '--log-bin=3s1-bin' to avoid this problem.
150422 22:59:17  InnoDB: Started; log sequence number 0 4071213443
150422 22:59:17 [Note] /usr/local/libexec/mysqld: ready for connections.
Version: '5.0.92-log'  socket: '/tmp/mysql.sock'  port: 3306  FreeBSD port: mysql-server-5.0.92
150423 18:15:54 [Note] /usr/local/libexec/mysqld: Normal shutdown

150423 18:15:55 [ERROR] /usr/local/libexec/mysqld: Sort aborted
150423 18:15:55 [ERROR] /usr/local/libexec/mysqld: Sort aborted
150423 18:15:59 [Warning] /usr/local/libexec/mysqld: Forcing close of thread 13077  user: 'xxxxx'

150423 18:15:59 [Warning] /usr/local/libexec/mysqld: Forcing close of thread 13076  user: 'xxxxx'

150423 18:15:59 [Warning] /usr/local/libexec/mysqld: Forcing close of thread 13075  user: 'xxxxx'