Weekly Development Summary

[Andrew Wilkins]

Hi all,

It's been a busy week as we continue towards the 2.2-rc1 release. As Tim
said earlier in the week, the release will slip to next week as we continue
ironing out the kinks. One of the main things we've been focusing on this
week is improving scalability and resilience in large deployments, such as
JAAS.

One major issue [0] fixed is that if we overflow the transaction log
collection in Mongo, the controller will now automatically restart to get
all of the watchers back into the appropriate state. A new controller
config attribute, "max-txn-log-size", has been introduced, which allows you
to change the transaction log collection size from the default of 10MB.

Another critical fix is to prevent resource-get from blocking indefinitely
when fetching the resource fails [1]. Juju will now retry fetching
resources for a set number of attempts, and then abort if it continues to
fail, giving the operator a chance to fix the charm resources or charm code
itself.

Work is underway to run one log forwarding worker per model, instead of one
per controller as we have now. This will enable us to optimise the way in
which logs are managed, to improve scalability and performance. Having
per-model log forwarders will also enable future improvements to support
forwarding logs to cloud-specific logging facilities.

A handful of other notable fixes:
 - better validation of custom simplestreams metadata [2]
 - simplified mongo oplog size calculation, to prevent frequent mongo
restarts [3]
 - fixed an issue with add-storage, where the specified pool was not used
in some cases [4]
 - several fixes [5] [6] for model migration related to resources

Last week, Ian mentioned that there would be a snap forthcoming containing
a preview of storage improvements scheduled for the 2.3 release. This was
sent out earlier this week, and we're waiting for feedback. If you have a
moment, please try it out and let us know what you think. Next week we'll
aim to release an update to the snap, with the next bits: adding
--attach-storage to add-unit, and automatically placing VMs in the same AZ
as the attached volumes (at least for AWS).

Thanks for reading!

Cheers,
Andrew

---

Quick links:
  Work Pending: https://github.com/juju/juju/pulls
  Recent commits: https://github.com/juju/juju/commits/develop

[0] https://bugs.launchpad.net/juju/+bug/1692792
[1] https://bugs.launchpad.net/juju/+bug/1627127
[2] https://bugs.launchpad.net/juju/+bug/1690456
[3] https://bugs.launchpad.net/juju/+bug/1677592
[4] https://bugs.launchpad.net/juju/+bug/1692729
[5] https://bugs.launchpad.net/juju/+bug/1692610
[6] https://bugs.launchpad.net/juju/+bug/1692646
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.ubuntu.com/archives/juju-dev/attachments/20170526/ad1d47d4/attachment.html>