> On 24 Jun 2015, at 00:17, Rajesh Kartha <[email protected]> wrote: > > One thing I noticed is when the stop is issued, all the HBase components go > away and the respective HBase components like Region server etc, logs does > not show the graceful shutdown messages that is typically seen. > > While there is stop command in the hbase_service.py script- I am not > seeing it being called.Does the Slider stop command simple requests the > containers to be killed ? How can one achieve a graceful shutdown of the > components ?
graceful managed shutdowns is one thing we've actually avoided so far, just killing containers instead. It's a bit of an over-strict adherence to the "crash only software" architecture https://www.usenix.org/legacy/events/hotos03/tech/full_papers/candea/candea.pdf ...but its based on the assumption that containers will be going away without warning anyway, a "yarn kill" will kill the application without warning, and when you turn pre-emption on then the rat of container failure can be even higher. That said, we've got the placeholders for having the agents run scripts to stop applications, they've just not been wired up to date. I think now with the rolling upgrade work -which includes stopping and starting applications in a single container, it's probably time to finish the wiring. of course, even with that: containers and apps will still go away without any warning...
