This is scoped to Swarming, I assume?

smut: What are the implications for switching the default image in MP to Trusty?

Rather than flipping Precise -> Trusty I think we should bring up Trusty VMs alongside Precise. Then we can remove Trusty VMs statically allocated in ccompute_config.py, and then we can dial up Trusty and dial down Precise in Machine Provider as needed.

CL to set up Trusty VMs on staging is out.

The following revision refers to this bug:
  https://chromium.googlesource.com/external/github.com/luci/luci-py.git/+/6996ed6741701ed5d69a62ccc0b52c5c9cd61830

commit 6996ed6741701ed5d69a62ccc0b52c5c9cd61830
Author: smut <smut@google.com>
Date: Fri Nov 11 22:05:32 2016

Support more specific descriptors of a machine's OS in Machine Provider dimensions

BUG= 664296 

Review-Url: https://codereview.chromium.org/2492953002

[modify] https://crrev.com/6996ed6741701ed5d69a62ccc0b52c5c9cd61830/appengine/components/components/machine_provider/dimensions.py

+1 on the plan. Thanks for taking care of this, Sana.

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config.git/+/ee96d3f0147651c0f406d3cfb491993d7c462cbf

commit ee96d3f0147651c0f406d3cfb491993d7c462cbf
Author: smut <smut@google.com>
Date: Fri Nov 11 22:44:28 2016

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infra/puppet/+/44166f2723f0161446588599a0d746028cf779df

commit 44166f2723f0161446588599a0d746028cf779df
Author: smut <smut@google.com>
Date: Tue Nov 15 22:35:09 2016

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config.git/+/f1c31273bdb84924965474f011a525789c754507

commit f1c31273bdb84924965474f011a525789c754507
Author: smut <smut@google.com>
Date: Wed Nov 16 02:24:22 2016

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config.git/+/c66601ad1041f1a68abbf530e9e8c5ca276345da

commit c66601ad1041f1a68abbf530e9e8c5ca276345da
Author: smut <smut@google.com>
Date: Thu Nov 17 23:13:41 2016

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infra/infra_internal.git/+/0bc957cb719a1416bb7d1c4abc8783329921c97c

commit 0bc957cb719a1416bb7d1c4abc8783329921c97c
Author: smut <smut@google.com>
Date: Tue Nov 22 00:27:21 2016

The following revision refers to this bug:
  https://chromium.googlesource.com/external/github.com/luci/luci-py.git/+/d5d2108ec34c507defdc28af67954f9eafe2e5d4

commit d5d2108ec34c507defdc28af67954f9eafe2e5d4
Author: smut <smut@google.com>
Date: Thu Nov 24 00:20:53 2016

Count instances managed by each instance template

BUG= 664296 

Review-Url: https://codereview.chromium.org/2520873003

[modify] https://crrev.com/d5d2108ec34c507defdc28af67954f9eafe2e5d4/appengine/gce-backend/instance_group_managers.py
[modify] https://crrev.com/d5d2108ec34c507defdc28af67954f9eafe2e5d4/appengine/gce-backend/instances.py
[modify] https://crrev.com/d5d2108ec34c507defdc28af67954f9eafe2e5d4/appengine/gce-backend/metrics.py

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config.git/+/78137639f4c66de7854d26833341566d224ee6c5

commit 78137639f4c66de7854d26833341566d224ee6c5
Author: smut <smut@google.com>
Date: Fri Dec 02 22:45:38 2016

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infra/infra_internal.git/+/ade618e4e3957deda536dd05e388f62bb7e8d2d1

commit ade618e4e3957deda536dd05e388f62bb7e8d2d1
Author: smut <smut@google.com>
Date: Mon Dec 05 21:44:33 2016

 Issue 664301  has been merged into this issue.

Issue 691736 has been merged into this issue.

 Issue 441429  has been merged into this issue.

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/ccf5f36a76e5cb2b93a51da01e0311b285bb5433

commit ccf5f36a76e5cb2b93a51da01e0311b285bb5433
Author: smut <smut@google.com>
Date: Mon Feb 13 23:38:39 2017

Changed issue dependency, it was reversed.

This issue shall be fixed in two steps:
1) create a CL to change the following files:
https://chrome-internal.googlesource.com/infradata/config/+/master/configs/gce-backend/templates.cfg
https://chrome-internal.googlesource.com/infradata/config/+/master/configs/gce-backend/managers.cfg

to migrate the bulk of the VMs from gce-precise to gce-trusty over the weekend.

2) Remove all Ubuntu-12.04 references to close this bug.

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/d7a37644163c367d34b5a67f7ca20332ee9e7c1e

commit d7a37644163c367d34b5a67f7ca20332ee9e7c1e
Author: smut <smut@google.com>
Date: Tue Feb 14 23:00:27 2017

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/d7a37644163c367d34b5a67f7ca20332ee9e7c1e

commit d7a37644163c367d34b5a67f7ca20332ee9e7c1e
Author: smut <smut@google.com>
Date: Tue Feb 14 23:00:27 2017

-1 work on the weekend. Dirk and today's trooper Robbie seem fine with switching this during the day so it's happening now.

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/f02c45acb2a2eb9f08ab00db9aae77584e8218d7

commit f02c45acb2a2eb9f08ab00db9aae77584e8218d7
Author: smut <smut@google.com>
Date: Wed Feb 15 00:54:44 2017

Botmap showed slave34-c1 just spun up with Precise(12.04).  It's in master.chromium.swarm.  Is this expected?  Would you like us to respawn it as a Trusty instance?

Yes, this is expected. We had to roll back the upgrade for swarming because some of the larger test suites were unexpectedly much much slower on trusty. And we're digging into that now.

I think we can roll forward again, though we probably shouldn't do that until Monday :).

I'm out Monday, I'll pull the trigger Tuesday.

sounds good, thanks!

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/7faeab0c86732d6da63ddb3c4055f629523801b8

commit 7faeab0c86732d6da63ddb3c4055f629523801b8
Author: smut <smut@google.com>
Date: Tue Feb 28 22:57:52 2017

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/edc88ab3e16522b8ff221d34690a92367fa098a6

commit edc88ab3e16522b8ff221d34690a92367fa098a6
Author: smut <smut@google.com>
Date: Thu Mar 02 02:41:13 2017

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/87625e306b78a9e96b50531287139f3b12da3ad0

commit 87625e306b78a9e96b50531287139f3b12da3ad0
Author: smut <smut@google.com>
Date: Tue Mar 21 22:50:49 2017