On Fri, Apr 18, 2014 at 1:12 AM, Imesh Gunaratne <[email protected]> wrote:
> Hi, > > During last few days we noticed an intermittent issue in scale down logic > and it was reported in STRATOS-614. > > Today after doing some thorough tests we identified the cause of this > issue. The problem was with the topology event receiver queue. Since this > queue was designed as a singleton, > Singletons should be avoided as much as possible, and used with caution. Some even consider it an anti-pattern. > it was being shared among multiple event receivers in Single JVM mode. As > a result event messages were unevenly being dequeued to message processors > and some event receivers were missing events randomly. > > This problem was also there in Tenant event receiver, Health Stat event > receiver and Instance Notifier event receiver. I have now fixed this by > introducing a message queue for each event receiver instance created. > > I have now committed this fix to master branch. Will do few more flow > tests to verify the correction and update with the results soon. > > Thanks > > -- > Imesh Gunaratne > > Technical Lead, WSO2 > Committer & PPMC Member, Apache Stratos > -- *Afkham Azeez* Director of Architecture; WSO2, Inc.; http://wso2.com, *Member; Apache Software Foundation; **http://www.apache.org/*<http://www.apache.org/> *email: **[email protected]* <[email protected]> * cell: +94 77 3320919 blog: **http://blog.afkham.org*<http://blog.afkham.org> *twitter: **http://twitter.com/afkham_azeez*<http://twitter.com/afkham_azeez> * linked-in: **http://lk.linkedin.com/in/afkhamazeez <http://lk.linkedin.com/in/afkhamazeez>* *Lean . Enterprise . Middleware*
