Icehouse-2 velocity analysis

Looking at our recently-concluded icehouse-2 development timeframe, we landed far less features and bugfixes than we wanted and expected. That created concerns about us losing our velocity, so I run a little analysis to confirm or deny that feeling.

Velocity loss ?

If we compare icehouse to the havana cycle and focus on implemented blueprints (not the best metric), it is pretty obvious that icehouse-2 was disappointing:

havana-1: 63
havana-2: 100
icehouse-1: 69
icehouse-2: 50

Using the first milestone as a baseline (growth of 10% expected), we should have been at 110 blueprints, so we are at 45% of the expected results. That said, looking at bugs gives a slightly different picture:

havana-1: 671
havana-2: 650
icehouse-1: 738
icehouse-2: 650

The first milestone baseline again gives a 10% expected growth, which means the target was 715 bugs... but we "only" fixed 650 bugs (like in havana-2). So on the bugfixes front, we are at 91% of the expected result.

Comparing with grizzly

But havana is not really the cycle we should compare icehouse with. We should compare with another cycle where the end-of-year holidays hit during the -2 milestone development... so grizzly. Let's look at the number of commits (ignoring merges), for a number of projects that have been around since then. Here are the results for nova:

nova grizzly-1: 549 commits
nova grizzly-2: 465 commits
nova icehouse-1: 548 commits
nova icehouse-2: 282 commits

Again using the -1 milestone as a baseline for expected growth (here +0%), nova in icehouse-2 ended up at 61% of the expected number of commits. The results are similar for neutron:

neutron grizzly-1: 155 commits
neutron grizzly-2: 128 commits
neutron icehouse-1: 203 commits
neutron icehouse-2: 110 commits

Considering the -1 milestones gives an expected growth in commits between grizzly and icehouse of +31%. Icehouse-2 is at 66% of expected result. So not good but not catastrophic either. What about cinder ?

cinder grizzly-1: 86 commits
cinder grizzly-2: 54 commits
cinder icehouse-1: 175 commits
cinder icehouse-2: 119 commits

Now that's interesting... Expected cinder growth between grizzly and icehouse is +103%. Icehouse-2 scores at 108% of the expected, grizzly-based result.

keystone grizzly-1: 95 commits
keystone grizzly-2: 42 commits
keystone icehouse-1: 116 commits
keystone icehouse-2: 106 commits

That's even more apparent with keystone, which had a quite disastrous grizzly-2: expected growth is +22%, Icehouse-2 is at 207% of the expected result. Same for Glance:

glance grizzly-1: 100 commits
glance grizzly-2: 38 commits
glance icehouse-1: 98 commits
glance icehouse-2: 89 commits

Here we expect 2% less commits, so based on grizzly-2 we should have had 37 commits... icehouse-2 here is at 240% !

In summary, while it is quite obvious that we delivered far less than we wanted to, due to the holidays and the recent gate issues, from a velocity perspective icehouse-2 is far from being disastrous if you compare it to the last development cycle where the holidays happened at the same time in the cycle. Smaller projects in particular have handled that period significantly better than last year.

We just need to integrate the fact that the October - April cycle includes a holiday period that will reduce our velocity... and lower our expectations as a result.