When we make a Major Update available, all users at least see the Major Update offer. Right? Well, actually, not always.
- When we make a major update offer available, only some of our users see the major update offer at all.
- For users who might see a major update offer, they only have the potential to see the major update offer *until* we next make a new minor update available. At that point, the major update offer is effectively disabled / turned off for all users.
For the longer answer, make some coffee and read on!
First, to set context, here’s a diagram showing what we did for FF2, including the 3 different major update offers.
With that in mind, lets start by looking at a straightforward case:
- Mozilla makes FF188.8.131.52 -> FF184.108.40.206 updates available
- User upgrades from FF220.127.116.11 -> FF18.104.22.168
- Mozilla make FF22.214.171.124 -> FF3.0.1 major update available
- User see MU offer from FF126.96.36.199 -> FF3.0.1
- some users upgrade to FF3.0.1, some stay on FF188.8.131.52
All that worked as expected. Now, lets revisit that scenario to find some “gotchas”.
1) User never sees the major update offer because they are on an untargeted older (or newer!) dot release.
- Mozilla makes FF184.108.40.206->FF3.0.1 major update available, targeting users on the latest available FF220.127.116.11 release.
- By design, this major update is only visible to FF18.104.22.168 users, so FF22.214.171.124 users will not see this major update offer.
- Once FF126.96.36.199 is available, and users move to FF188.8.131.52, there is no way for those FF184.108.40.206 users to go back to see the FF220.127.116.11->FF3.0.1 major update.
- A user on FF18.104.22.168 needed to wait until we produced FF22.214.171.124, upgrade to FF126.96.36.199, wait for us to produce a new major update offer from FF188.8.131.52, and then react to that new major update offer before we release FF184.108.40.206.
- Similarly, once FF220.127.116.11 is available, users on FF18.104.22.168 can only upgrade to FF22.214.171.124; they are forced to skip over FF126.96.36.199, and are never given a chance to see the major update offer.
- Today (03mar2009), we currently only have major update visible to FF188.8.131.52 users. This is important because according to today’s metrics data, 49% of our FF2 users are not on FF184.108.40.206. This means that 49% of FF2 users cannot even see our major update offer to move to FF3.0.5:
06.1M (51%) FF220.127.116.11 users who can see major update offer
05.8M (49%) other FF2 users who cannot see major update offer
11.9M total FF2 users
Summary: major update targets upgrading users from a specific dot release. If a user is not on that specific dot release, they don’t see the offer.
2) Some users never sees the major update offer, even if they are on the targeted dot release, because of a race condition.
- Mozilla makes FF18.104.22.168->FF3.0.1 major update available
- This major update is only visible to FF22.214.171.124 users, so FF126.96.36.199 users do not see this.
- Mozilla makes FF188.8.131.52->FF184.108.40.206 updates available
- Existing FF220.127.116.11 users no longer see major update offer, and can now only see the update to FF18.104.22.168.
- Any FF22.214.171.124 users who had their browser turned off long enough would miss this time window, and never see the major update offer at all.
Summary: The only users who can see the major update offer were using FF126.96.36.199 between the time the major update was first made available, and the time FF188.8.131.52 was released.
Hopefully all that made sense. Its tricky to explain without hand-waving in front of a whiteboard, so please let me know if you have any questions.
Finally, I’d really love to hear any suggestions people have on what we could do differently, so that more users see these major update offers?
UPDATE: I accidentally dropped some important disclaimers. See this follow-on blogpost for details. Sorry for any confusion. John 06mar2009