Servicing comes to the Slow ring

Something very interesting has happened to Windows 10 Insiders Preview builds in the Slow ring over the past few months. They’re being released more regularly and with increased reliability. It’s all part of a commitment we made earlier this year to start servicing the Slow ring.

This is especially good news for businesses who use Windows 10 Insider Preview Builds to get an early start on their Windows validation efforts—and this good news is only going to get better.

Understanding the current state of our rings

Insider Preview builds are released to Windows Insiders in three rings, Fast, Slow, and Release Preview. If you have devices in the Fast ring, you’re getting our earliest Insider Preview builds. The Fast ring is a great place to explore next features, but there is potential for issues.

At the other end of the ring spectrum is the Release Preview ring, which is essentially the current public branch of Windows 10, but with early access to updates, applications, and drivers.

Builds in the Slow ring are ideal for users who want to see new features, but not run the risk of really bad issues. It provides new updates and features, but its builds are more stable than those in the Fast ring. This makes the Slow ring the perfect place for feature exploration and longer running validation tests, as well as app and infrastructure validation.

The problem is getting Fast ring builds up to Slow ring quality often takes us longer than we anticipated. Adding to the delays, the builds we created to fix bugs would sometimes introduce new bugs or issues. As we approached the end of a development cycle and the quality of builds increased, we could also increase the frequency of our Slow ring releases. But, we want to get builds out to Insiders earlier to give you a bigger testing window. At the same time, we also want to make sure that every build is stable enough to run on a day-to-day basis without losing productivity.

To achieve both objectives, it was clear that we needed to do things differently.

Servicing as a solution

Several months ago at our Microsoft Build event, we made the important announcement that Insider Preview builds in the Slow ring would be serviced now. Not only that, they’ll be serviced using the same tools and processes we use to support our production releases.

Instead of using feature updates, which are entirely new builds, to address bugs, we’re now creating fixes, packaging them up as quality updates, and releasing them along with the feature update. It took us some time to get the process right, but it’s paid off. Bugs are now caught sooner and fixed faster, so stable builds can be released earlier. Here’s how this system works:

  1. We evaluate the quality of builds in Fast. We look at the quality of Fast ring builds on a daily basis using feedback from internal self-hosting and Windows Insiders.
  2. We triage any proposed bugs blocking Slow. We send bugs blocking a Slow ring release to the feature teams, who get issues fixed and into the branch in 3 to 5 days. Once checked in, the fixes are packaged into the latest cumulative update (LCU).
  3. We test and deliver the serviced Slow build to Windows Insiders. We do another round of internal self-host testing of the build with the LCU fixes to make sure everything is working. The feature update and service packages (quality update) are then delivered to the Slow ring at the same time.

Steps showing from Fast ring, to Fixed, to Slow ring

What this means for Windows Insiders

With the new servicing mechanism, we can now deliver several benefits to Windows Insiders:

  • We can stabilize a Fast ring build even in the early stages of a release cycle and send it to the Slow ring right way. In fact, you’ll start seeing builds in the Slow ring earlier than ever before in our upcoming 19H1 release cycle.
  • All builds will receive the latest Microsoft Security Response Center (MSRC) security fixes shortly after they’re publicly available. We will align to InMarket B releases, or Patch Tuesday builds.
  • We commit to selecting a build and stabilizing it with certain fixes to bring it up to the quality needed for the Slow ring once a month.
  • We will aspire to take all Fast builds to Slow if they meet the quality bar.

And we’re not done yet. We’re continue to refine our servicing to bring you even greater speed and stability in the Slow ring. We’re also making updates smaller and easier to deploy.

Now more than ever, Insider Preview builds are the perfect way to get a head start on your next Windows deployment. Start by taking a fresh look at your Windows as a Service strategy. Use Slow ring builds on at least 1% of your devices to effectively validate apps and infrastructure. Then get ready to get even more from your Windows investment.

As you’ll soon discover, it pays to think Slow!