Comment 0 for bug 1645729

We recently upgraded a few environments to 1.25.8 and we started experiencing problems on some of them.

What we know so far:
* the problems only affects bigger environments, 8-10 machines and bigger. Smaller environments look stable
* on the problematic environments jujud uses lots of memory on node 0, for example nearly 1GB RES on bootstrap node with 2GB RAM
* we see "lost" agents ocassionally. It's intermittent, sometimes environments are fine for hours
* occasionally hooks end up in error state, we see error like this in the logs:
2016-11-29 09:30:29 ERROR juju.api.watcher watcher.go:84 error trying to stop watcher: connection is shut down
2016-11-29 09:30:29 ERROR juju.api.watcher watcher.go:84 error trying to stop watcher: connection is shut down
2016-11-29 09:30:29 ERROR juju.worker.uniter.filter filter.go:137 watcher iteration error: Closed explicitly
2016-11-29 09:30:29 ERROR juju.api.watcher watcher.go:84 error trying to stop watcher: connection is shut down
2016-11-29 09:30:29 ERROR juju.api.watcher watcher.go:84 error trying to stop watcher: connection is shut down

juju version is 1.25.8, running on amd64 trusty guests.