I'm using Hibernate and Tomcat JDBC connection pool to use my MySQL DB.
When, from any reason, the DB is down, my application got stuck.
For example, I have REST resources (with Jersey), they are not getting any requests.
I also using quartz for schedule tasks, they aren't running as well.
When I start my DB again, everything goes back to normal.
I don't even know where to start looking, anyone has an idea?
Thanks
Asked
Active
Viewed 133 times
-2
danieln
- 4,795
- 10
- 42
- 64
2 Answers
0
What must be happening is your application must be receiving request but there must be some exception while establishing database connection .see the logs.
try some flow where your are not doing any database operation. It must work fine.
M Sach
- 33,416
- 76
- 221
- 314
-
This won't be the case if all available application server request processing threads are already hung as a result of the database problem – DaveH Aug 15 '13 at 12:24
0
When the application has hung, get a thread dump of the JVM, this will tell you the state of each thread and, rather than guessing as to the cause, you'll have concrete evidence.
Having said that, and going with the guess work approach, a lot comes down to how your connection pool is configured and the action your code takes when it receives the SQLException. If the application is totally hung, then my first port of call would be to find out if the db accessing threads are in a WAIT state, or even deadlocked. The thread dump will help you to determine if that is the case.
see kill -3 to get java thread dump for how to take a thread dump
