Larry, On 11/16/15 5:08 PM, Cohen, Laurence wrote: > Thank you Christopher. I'm going to start with the thread dump since we > are using jdk and that appears very straightforward. Part of my dilemma is > that the problem is occurring on a private network where I do not have > access to the internet.
You could have your 'wget' script trigger a jstack before bouncing Tomcat. That way, you don't have to have quick access to the server when it starts misbehaving. > Our public facing application with the same exact > build is not experiencing this problem, so I'm wondering if this is a > network issue on the private side. I'll start here though. It's nice that it's not the other way around. It's *usually* the other way around: dev/test is juuuuust fine but prod is hosing all over the place. -chris > On Mon, Nov 16, 2015 at 4:55 PM, Christopher Schultz < > ch...@christopherschultz.net> wrote: > >> Larry, >> >> On 11/16/15 4:42 PM, Cohen, Laurence wrote: >>> Are there any tools that come with Java that I can use to troubleshoot an >>> intermittent problem we are having? The problem is that several times a >>> day, our Tomcat applications will stop responding and I'll have to >> restart >>> them to get them working again. It's gotten to the point where I have >>> written a script which does a wget every 10 minutes against an object in >>> the DB, and if it fails, it will restart our apps. >> >> Consider using a real monitoring tool. There are some free ones >> available, such as Nagios and ighinga, that aren't much more complicated >> than your wget script, except that they have alerting, history, etc. all >> built around them. They also let you sample LOTS of things. >> >>> I've also done some statistics gathering and imported them into a >>> spreadsheet so I can see what is going on at the time the system is >>> crashing. All I can see is that the Tomcat connections are spiking. >> >> Spiking to a particular limit? What does your connector configuration >> look like? And your deployment? >> >>> We are running Tomcat 7.0.59 with two apps, Postgres 9.2 on the backend >>> which is not administered by us, and httpd on the front end, 2.2.15. The >>> httpd server and app server are RHEL6. >> >> Just a single Tomcat instance? That narrows things down a bit. How are >> you reverse-proxying? mod_jk? mod_proxy_http? >> >> What does your JNDI DataSource configuration look like? >> >> Are you able to take a thread dump when the server seizes-up? >> >> http://wiki.apache.org/tomcat/HowTo#How_do_I_obtain_a_thread_dump_of_my_running_webapp_.3F >> >> This will tell you what the server is doing. I suspect you'll see a >> bunch of threads waiting on a database connection or something like that. >> >> -chris >> >> --------------------------------------------------------------------- >> 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
