We had a user (User A) starting the mysql client and it would take several seconds to load, the user felt that this just started out of the blue and hadn't done this before. It was causing a few scripts to time-out and there was a concern that it was an issue with the database itself. Upon investigation it was found that 'User B' could start the mysql client on the same server in a blink of an eye.
Given the above, we felt that ruled out an issue with the DB itself. We did verify that each user was using the same mysql client and had similar ENV/PATH setups.
After giving it some thought we had 'User A' to start the client in verbose mode, which gave us our answer.
-bash-4.3$ mysql --verbose -u userA -A Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 10410 Server version: 5.0.45 MySQL Community Server (GPL) Reading history-file /home/userA/.mysql_history <----------------- HERE IS THE ISSUE
So if we take a look at this history file of 'User A', it's a 160M file:
-bash-4.3$ ls -lh ~/.mysql_history -rw------- 1 userA staff 160M Jul 6 14:48 /home/userA/.mysql_history
Where as 'User B' had a much smaller file:
-bash-4.3 ls -lh ~/.mysql_history -rw------- 1 userB staff 53K Jul 6 14:42 /home/userB/.mysql_history
This may be a simple thing that others just new off the bat, but we wanted to document it here as our Google-Fu didn't reveal anyone else dealing with this type of issue.