-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Daniel,
On 2/3/14, 7:10 AM, Daniel Mikusa wrote: > On Feb 3, 2014, at 3:30 AM, Maor Yosef <maoryo...@gmail.com> > wrote: > >> Hi. >> >> 1. We are aware that 6.0.26 is old, but since there is a large >> operational impact, we wont upgrade the tomcat until we will know >> its definetly an issue in this specific version > > While I understand what you’re saying, I disagree. If you need to > sell the change to management, you should take a look at the > security problems that have been fixed since 6.0.26 and weigh the > cost of upgrading versus a security breach or manually applying > mitigations, if that’s even possible. > > http://tomcat.apache.org/security-6.html +1 >> 2. You are right, it was my mistake, it causes OOM and not stack >> overflow, when we see high sessions count we get exceptions >> saying "unable to create new native thread” > > This is telling you that there’s not enough memory to allocate any > more threads. > > 1.) Have you tried setting “-Xss”? This will set the thread stack > size, i.e. how much memory each thread has available for its > stack. Often times you don’t need nearly as much as the default > allocated by the JVM, so you can lower it and get more threads out > of the same available memory. Maybe try 256k or even lower. > You’ll know you went too low if you see StackOverflowErrors. > > 2.) How many threads are being created / used? Perhaps you’re > creating too many threads? You’ll probably want to do some > monitoring and see how many the Tomcat is creating / using and how > many your application is creating / using. Perhaps you’ve got a > problem where too many threads are being created or where threads > are being created and not properly cleaned up. Tools that could > help here: jconsole / jvisualvm or thread dumps I'd be interested in knowing why threads are being created at all. Thread dumps will reveal a lot of good information. >> 3. Looking at the sessions manager, we see a lot of sessions with >> a negative TTL - meaning they werent expired, if I manually >> expire them then the sessions count decreases. > > This doesn’t sound related, although it’s hard to say. Might be > helpful if you can include your configuration, minus comments. > >> 4. Can you point me to an article on how to configure different >> background thread for each container? is it configured in tomcat >> or should be implemented in the application? If your background thread is becoming stuck, you should fix *that* instead of trying to work-around it. Thread dump(s)? - -chris -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQIcBAEBCAAGBQJS7+VNAAoJEBzwKT+lPKRYcjkP/2A0gQ3HnJNOA2724kxHiYO/ q4ZLnqJUAnepPttDYu4eL8/sehnmLm1kNQ0q/vby+5LLXLeU3QldmJsZSHwDft7M +sph2hXy0Ed6a/3sS4nYEHLWYcIs9rEi13EkMTgvewE7jEp4QldTisfHi4I3XgDq ZlraHHQjvPgbYFwzQxmwg2F7+ag69GqR52q9zECC97tXctTPQHxd8hJ40298y40w 2HIyDV6l9EuPVkan1/g7xuWxRbWoAiwhawkiGA606r1IhtO7cB7C6ulAyDyoLKqj NEe1EHfVeDvmiavw7evIcknTVyK1hcuQC0NPV5bSMEQnQf6ZTWw67FQfosQUmqA2 L+kYtPKDzsnF9slUfgI7YokEjzApZx/dElsZUdgatIvb5yz8IFCXKaiFxkcHGffx TzHMe6EAiDZglM5fMQIPmvuS5p5/iaJ5mMTZzamcOZ2VOD1/RDtqQm5MLljd4M/0 cVpGb/xEEZLGoj8mnXTfQq+NFYbjkCA3PcglvoBi4VtgOS7pBykccEFEv+1HavHC h4ROzGJ8u7uHhGbUx2WbxHfkTtk6HGLon1bIyQkP1vraAdsOClAfiEto/C+bv9jw y5iLOfEEHlZTPCTv6lbDtYmTBaOO1r/3LQ12kc3eZfzjQaOuGUo7jwYc4A0yTDDJ 8V4q1aiF7dn26chh/BsS =R+5r -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
