2016-08-12 13:46 GMT+02:00 John Huss <johnth...@gmail.com>: > In every database I have used every query requires a transaction. Often > they will start them automatically if you don't do it explicitly.
Right , but I guess that Tomcat uses JDBC connections and I wonder why for executing validationQuery sentence, Tomcat doesn't use autocommit = true setting > On Fri, Aug 12, 2016 at 4:13 AM Jose María Zaragoza <demablo...@gmail.com> > wrote: > >> 2016-08-11 21:33 GMT+02:00 John Huss <johnth...@gmail.com>: >> > I have verified that in version 8.0.36 of tomcat jdbc the validation >> query >> > functionality does not commit the transaction it starts in order to run >> the >> > validation query, which can cause an open transaction for a very long >> time >> > (possibly until the database crashes). This seems to be especially >> > problematic if you have a large pool where the connections are idle for a >> > large period of time. >> > >> > I also tested against version 9.0.0M9, and in that version the problem is >> > fixed. However, nothing about this appears in the release notes for any >> > version (9.0, 8.5, or 8.0). If this bug has indeed been fixed it should >> be >> > documented in the release notes. Also, back-porting the fix to the 8.0 >> > branch would be very helpful. >> > >> > For the time being I am working around the problem by changing my >> > validation query from "SELECT 1" to be "SELECT 1; COMMIT" (using >> > postgresql). This prevents the issue. >> >> >> I wonder why a validationQuery needs to open a new transaction >> >> >> > >> > This was reported previously (three years ago) here: >> > >> https://mail-archives.apache.org/mod_mbox/tomcat-users/201301.mbox/%3CCAPw873vy%2B9kWMQiFPbnTX6g1FSQ8oTVhDJ3Zagp9UkUZ3d5qjw%40mail.gmail.com%3E >> > >> > Thanks, >> > John >> >> --------------------------------------------------------------------- >> 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
