I deployed my application to the Tomcat 5.5.26. I use hibernate for O/RM, and the connection pool is c3p0, the database is MySql 5.0.
Several days ago, the Database Server is down, but there are lots of user accessing the Tomcat. After I restarted the Database Server, the Tomcat can't connect to the Database Server automatically. And I have to restart the Tomcat manually. And only it was restarted, the Tomcat can connect to the Database Server. I checked logs, and found that there are lots of Select Operations in the log file, and there are some error about "deadlocked PoolThread". Does someone meet this problem before, and what's reason? Thanks. PS: the content of the log file: DEBUG 20091207 00:00:30,757 >>>>>>>>SELECT * FROM conTable WHERE Keyword = '172486' AND (Recip = '6590607447' OR Recip like '6590607447/type=t...@%' ) DEBUG 20091207 00:00:31,815 >>>>>>>>SELECT * FROM conTable WHERE Keyword = '605747' AND (Recip = '6707468443' OR Recip like '6707468443/type=t...@%' ) ............. DEBUG 20091207 00:00:35,813 >>>>>>>>SELECT * FROM conTable WHERE Keyword = '172486' AND (Recip = '6590607447' OR Recip like '6590607447/type=t...@%' ) ;;;;;;;;;;;;;;;;; DEBUG 20091207 00:00:36,334 >>>>>>>>SELECT * FROM conTable WHERE Keyword = '160564' AND (Recip = '525510099023' OR Recip like '525510099023/type=t...@%' ) WARN 20091207 00:00:39,282 Task com.mchange.v2.resourcepool.basicresourcepool$acquiret...@13ba7d (in deadlocked PoolThread) failed to complete in maximum time 60000ms. Trying interrupt(). WARN 20091207 00:00:39,282 Task com.mchange.v2.resourcepool.basicresourcepool$acquiret...@1386abc (in deadlocked PoolThread) failed to complete in maximum time 60000ms. Trying interrupt(). WARN 20091207 00:00:39,282 Task com.mchange.v2.resourcepool.basicresourcepool$acquiret...@e78f88 (in deadlocked PoolThread) failed to complete in maximum time 60000ms. Trying interrupt().
