Searching back through some old mail I see something similar has surfaced before in this bug report: https://bugs.launchpad.net/dhis2/+bug/534567
Also there was an issue with one of the servers in India which also used mysql where I had a look at the log file and found an inexplicably large number of threads blocked in a write operation which I now suspect is also related. It seems that some care needs to be taken to manage the mysql connection pool over time. And as I suggested above I believe (suspect!) the way to do that might be to proactively manage the connection threads using c3p0's idleTestperiod property. Note I am no hibernate or c3p0 expert. I do recall from the "old days" perhaps around 2.01 we were commonly setting c3p0 related properties in the hibernate.properties file. I also remember (but can't find a reference) some suggestion of dropping this. Lars, do you remember why we don't have these parameters set in the hibernate.properties any more? I have a funny feeling that they are required to keep long running mysql installations alive and kicking. Regards Bob On 5 July 2010 17:39, Orvalho Augusto <[email protected]> wrote: > Thanks for help. > > Postgres I will use if I do not have a solution. > > I will try things on the connection pool. > > One very important note: > I have used DHIS 2.01 for almost a year and never happened to have these > errors on the same Fedora Server as described before. I have tried some > snapshot versions and again never had this. > I jumped from 2.01 to 2.04 and I start with MySQL troubles. > > Caveman > > > On Mon, Jul 5, 2010 at 10:20 AM, Bob Jolliffe <[email protected]> wrote: >> >> Hi Orvalho >> >> Whereas I do agree postgres might solve your problems it does seem >> like a drastic solution to this problem. The fact is mysql does >> actually work and apparently work well so it should be possible to >> solve this. >> >> Trying to think logically here ... you have another similar setup >> where everything seems ok. I suppose the load could be quite >> different on the two servers, but lets discount that for a bit. If >> you are reusing old stale and broken connections then the only three >> places i can think to look are: >> (i) the jdbc driver (version compatibility). I think you checked that. >> (ii) tcp/ip problems >> (iii) the connection pool >> >> Regarding (ii) can you check the value of bind-address in >> /etc/mysql/my.cnf (or whatever config file you are using). This >> should be set to 127.0.0.1 unless you are connecting to the db from a >> different host. At least this interface will always be up so you >> shouldnt get intermittent network errors on it. >> >> Regarding (iii) I suggest (as above) that you look at setting up c3p0 >> parameters to periodically test and discard stale connections. Does >> anybody (maybe Indian team) have a good sample config? >> >> Regards >> Bob >> >> On 4 July 2010 13:09, Orvalho Augusto <[email protected]> wrote: >> > It will give some job because we developed a tool to convert data from >> > one >> > database to MySQL. >> > >> > It is the only thing I can try to do to solve. >> > >> > Caveman >> > >> > >> > >> > On Sun, Jul 4, 2010 at 8:16 AM, Knut Staring <[email protected]> wrote: >> >> >> >> Is postgres out of the question? >> >> >> >> On Jul 4, 2010 5:59 AM, "Orvalho Augusto" <[email protected]> wrote: >> >> >> >> I do not know what to do. I have found this: >> >> >> >> >> >> http://dev.mysql.com/doc/refman/5.1/en/connector-j-usagenotes-troubleshooting.html >> >> >> >> And what makes me feel really bad is: >> >> "22.3.5.3.4: I have a servlet/application that works fine for a day, >> >> and >> >> then stops working overnight MySQL closes connections after 8 hours of >> >> inactivity. You either need to use a connection pool that handles stale >> >> connections or use the "autoReconnect" parameter" >> >> >> >> and >> >> "The autoReconnect facility is deprecated, and may be removed in a >> >> future >> >> release. " >> >> >> >> >> >> So what we do? >> >> >> >> Caveman >> >> >> >> On Mon, Jun 28, 2010 at 12:59 PM, Bob Jolliffe <[email protected]> >> >> wrote: > > Hi > > It looks... >> >> >> >> _______________________________________________ >> >> Mailing list: https://launchpad.net/~dhis2-devs >> >> Post to : [email protected] >> >> Unsubscribe : https://launchpad.net/~dhis2-devs >> >> More help : https://help.launchpad.net/ListHelp >> >> >> > >> > >> > >> > > > > > _______________________________________________ Mailing list: https://launchpad.net/~dhis2-devs Post to : [email protected] Unsubscribe : https://launchpad.net/~dhis2-devs More help : https://help.launchpad.net/ListHelp
