Hi Mark,
> -----Original Message----- > From: Mark Thomas <ma...@apache.org> > Sent: Wednesday, May 29, 2024 10:10 AM > To: users@tomcat.apache.org > Subject: Re: Database Connection Requests Initiated but Not Sent on the Wire > (Some, Not All) > > On 29/05/2024 13:38, Eric Robinson wrote: > >> -----Original Message----- > >> From: Mark Thomas <ma...@apache.org> > > <snip/> > > >> I intend to wok on a patch for Tomcat that will add caching that > >> should speed things up considerably. I hope to have something for > >> Eric to test today but it might take me until tomorrow as I have a > >> few other time critical things fighting to get tot he top of my TODO list > >> at the > moment. > >> > >> > >> Moving the JDBC driver JARs from WEB-INF/lib to $CATALINA_BASE/lib > >> may also be a short-term fix but is likely to create problems if the > >> same JAR ever exists in both locations at the same time. > > Just an FYI. On further reflection, moving the JDBC driver JARs isn't going to > help. Sorry. You'll need my fix. > > Assuming, of course, you are willing to test a patch to address this on a > production system. > Absolutely. We and the users are ready to do what it takes. > > That's some great sleuthing and the explanation makes a ton of sense. It > leaves me with a couple of questions. > > > > If you are correct, then it follows that historic activity has been hovering > dangerously near the threshold where this symptom would manifest. Within the > past month, an unknown change in the system climate now causes an uptick in > the number of DB requests/second at roughly the same time daily (with > occasional exceptions) and the system begins to trip over its own feet. I > haven't > seen anything in my Zabbix graphs that stood out as potentially problematic. > Armed with this information, I am now taking a closer look. > > Ack. > > > The natural next question is, what changed in the application or the users' > workflow to push activity over the threshold? We'll dig into that. > > Could be all sorts of things. > > It might just have been coincidence the first time and now the users all > request > the data they need at the start of their day in case the problem happens > again. > And by doing that they cause the very problem they are trying to avoid. > One of the webapps is related to voice reminder messages that go out to people. The reminders go out sometime after 9 am, which tracks with the slowdowns. > Mark > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org Disclaimer : This email and any files transmitted with it are confidential and intended solely for intended recipients. If you are not the named addressee you should not disseminate, distribute, copy or alter this email. Any views or opinions presented in this email are solely those of the author and might not represent those of Physician Select Management. Warning: Although Physician Select Management has taken reasonable precautions to ensure no viruses are present in this email, the company cannot accept responsibility for any loss or damage arising from the use of this email or attachments.
