Look at the current number of idle VMs during resize logic

Look at the current number of idle VMs during resize logic

targetSize includes all VMs that are being created, deleted, etc. By looking only at idle VMs we actually wait for them to be created before flooding GCE with another increase request.

BUG=620534
Committed: https://github.com/luci/luci-py/commit/f10f1d7b962785a2f2f3a44bbdc2657beb02cdf8

[smut, 2016-07-20 20:55:20]

smut@google.com changed reviewers:
+ vadimsh@chromium.org

[smut, 2016-07-20 20:55:21]

So for example if it gets stuck resizing from 100 -> 200 we want to wait for it
to actually reach 200 before adjusting up to 300.

[Vadim Sh., 2016-07-20 20:57:23]

https://codereview.chromium.org/2163413002/diff/1/appengine/gce-backend/insta...
File appengine/gce-backend/instance_group_managers.py (right):

https://codereview.chromium.org/2163413002/diff/1/appengine/gce-backend/insta...
appengine/gce-backend/instance_group_managers.py:312: # Find out how many VMs
are created (i.e. not currently being created
"are idle" ?

https://codereview.chromium.org/2163413002/diff/1/appengine/gce-backend/insta...
appengine/gce-backend/instance_group_managers.py:315: if not current_size:
zero idle VMs is not allowed?..

should it be "if current_size is None"?

[smut, 2016-07-20 21:00:37]

https://codereview.chromium.org/2163413002/diff/1/appengine/gce-backend/insta...
File appengine/gce-backend/instance_group_managers.py (right):

https://codereview.chromium.org/2163413002/diff/1/appengine/gce-backend/insta...
appengine/gce-backend/instance_group_managers.py:312: # Find out how many VMs
are created (i.e. not currently being created
On 2016/07/20 20:57:23, Vadim Sh. wrote:
> "are idle" ?

Done.

https://codereview.chromium.org/2163413002/diff/1/appengine/gce-backend/insta...
appengine/gce-backend/instance_group_managers.py:315: if not current_size:
On 2016/07/20 20:57:23, Vadim Sh. wrote:
> zero idle VMs is not allowed?..
> 
> should it be "if current_size is None"?

True story. Probably not necessary anyway, unless GCE randomly changes their
response structure.

[Vadim Sh., 2016-07-20 21:02:03]

lgtm

[smut, 2016-07-20 21:16:35]

The CQ bit was checked by smut@google.com

[commit-bot: I haz the power, 2016-07-20 21:16:42]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-20 21:18:58]

Description was changed from

==========
Look at the current number of idle VMs during resize logic

targetSize includes all VMs that are being created, deleted, etc. By looking
only at idle VMs we actually wait for them to be created before flooding GCE
with another increase request.

BUG=620534
==========

to

==========
Look at the current number of idle VMs during resize logic

targetSize includes all VMs that are being created, deleted, etc. By looking
only at idle VMs we actually wait for them to be created before flooding GCE
with another increase request.

BUG=620534

Committed:
https://github.com/luci/luci-py/commit/f10f1d7b962785a2f2f3a44bbdc2657beb02cdf8
==========

[commit-bot: I haz the power, 2016-07-20 21:18:59]

Committed patchset #2 (id:20001) as
https://github.com/luci/luci-py/commit/f10f1d7b962785a2f2f3a44bbdc2657beb02cdf8