On 13 May 2010, at 11:13, "Tomás Tormo" <tto...@indenova.com> wrote:
>> >> http://commons.apache.org/dbcp/configuration.html >> > Thanks, I was already checking that. > >> I don't know anything about Introscope. > It just an monitoring tool application > >> If maxActive is larger than the number of active connections, then >> there's nothing wrong there, is there? I'm not sure what you're >> trying >> to explain by that. >> >> > Yes maxActive is larger than the active connections. Both queries > (the one running and the one stalled) are trying to access the same > register in BBDD (is the case when two different users are doing the > same), but the query is just a simple SELECt, that's why I think is > surprising that the second one is getting stalled... > >> If you can see some stalled connections, take a thread dump to see >> what >> they're doing/waiting on. > > Could I use jvisualvm for that? I knew I could see threads state > there, but I didn't know I could see why they are waiting... Yes, or jstack on the command line. > Sorry for my ignorance, I'm just starting in this field... Gotta start somewhere. :) p > > > > On 13/05/10 11:05, Pid wrote: >> On 13/05/2010 09:35, Tom�s Tormo wrote: >> >>> Greetings >>> >>> I would like to understand correctly how Tomcat database pool works. >>> >> It's a repackaged version of Apache Commons DBCP. >> >> >>> As I understand, when the application starts, a pool connection is >>> created with *initialSize* connections (0 by default). >>> >>> Later on, new connections are created on demand of the application, >>> untill it reaches the *maxActive* connections. If *maxActive* has >>> been >>> reached and the application requests for a new connection, the >>> pool will >>> wait *maxWait* milliseconds for a free connection. >>> >>> If any connection has been released, it will be kept as idle as >>> long as >>> *maxIdle* is not reached. No more connections will be created if >>> there >>> are *minIdle* or more connections in the pool in idle state. >>> >> http://commons.apache.org/dbcp/configuration.html >> >> >>> �Am I right? >>> >>> But I still have some questions: >>> >>> �How to see the pool connection state in real time? (idle conn >>> ections, >>> active connections, etc). We are using Introscope for monitoring an >>> application, and we can see some stalled connections... but the >>> maxActive parameter is far bigger (100) than the actived connections >>> shown by Introscope (24). This is happening with Tomcat 5.5 on >>> CentOs >>> using Java 1.6. >>> >> I don't know anything about Introscope. >> >> If maxActive is larger than the number of active connections, then >> there's nothing wrong there, is there? I'm not sure what you're >> trying >> to explain by that. >> >> If you can see some stalled connections, take a thread dump to see >> what >> they're doing/waiting on. >> >> >> p >> >> >> > > > -- > Un saludo, > > Tom�s Tormo Franco > Area de sistemas > > INDENOVA S.L. > C/ Dels Traginers 14, 2� B > Pol�gono Vara de Quart > 46014 Valencia > Tel. (34) 96 381 99 47 > Fax. (34) 96 381 99 48 > > tto...@indenova.com > http://www.indenova.com > > Desc�rguese gratuitamente el software eSigna Viewer para > visualizar documentos firmados electr�nicamente: > http://www.indenova.com/eSignaViewer. > php > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
