On Friday 01 October 2004 4:29 pm, Kumar, Sunitha wrote: > What command did you use to generate the thread dump?
I'm in Linux, so I used kill -QUIT <pid> where <pid> was the process ID. --Kaleb > -sunitha > > -----Original Message----- > From: Kaleb Pederson [mailto:[EMAIL PROTECTED] > Sent: Friday, October 01, 2004 3:08 PM > To: Tomcat Users List > Subject: Tomcat becoming almost completely non-responsive > > > Hello, > > I have an interesting problem. After a while, tomcat (5.0.27) becomes > almost > completely non-responsive. If I telnet in to port 8009 (I'm using > apache > and mod_jk2), I get no response, at least not within the default > timeout. If > a browse to a page, I will generally, after about 4-5 minutes, see a > page > returned. > > To narrow down the slowness, I generated a full thread dump, and found > the > following information: > > [ see attachment for more info] > Total threads: 180 > executeQuery: 2 // executing a db query > validateConnection: 0 // trying to validate their connection > validateObect: 48 // in > commons.dbcp.PoolableConnectionFactory.validateObject > socketAccept: 3 // accepting a socket > socketRead0: 10 // reading a socket > ReferenceQueue: 1 > ThreadPool$MonitorRunnable: 2 > borrowObject and Object.wait: 85 // trying to get an object from the > pool > Object.wait: 20 // threads just waiting around > Remaining: 9 // misc. threads > > My database connection is setup so that I have 50 allowed connections, > which > matches my 48 in validateObject and 2 executing queries. However, when > I > query the database status, I see 2 active threads and the rest are > 'sleeping', just waiting around, as they would be if the connection pool > > hadn't released them yet. > > So, why would there be 48 connections that seemed locked and weren't > querying > the DB? And then the other 85 that were seemingly waiting on the 45? > Any > ideas what might be going on? The DB is ready? I have log abandoned > turned > and an haven't seen a problem yet. If the load drops sufficiently on > the > server, everything eventually returns back to normal, otherwise it takes > 5-10 > minutes to get a response from the server. > > I have attached an abbreviated form of the thread dump which should > provide > all the critical information and can provide as much other information > as is > necessary. > > Thanks for the help. *All* suggestions welcome ;) > > --Kaleb > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
