Mozilla released Firefox3a8 on Thursday, 20-sep-2007, at 08:30am PST.

This was a manual build run (not automated on trunk yet), and an alpha release (not a high-priority security release), so the numbers are quite different to the earlier Firefox2.0.0.7 release. Even as an apples-to-baseballs comparison, I thought the numbers were interesting and worth sharing. From “code freeze” to “available for public download” was 14.33 days wall-clock time. Of that time Build&Release took 2.25 days (55 hours including the respin).

00:01 06-sept: M8 code freeze, tree closed
18:48 11-sept: Dev verifies last fix landed, and gives “go” to build
20:46 11-sept: Build starts building
01:26 12-sept: blocker bug#395862 filed
08:40 12-sept: blocker patch landed
09:22 12-sept: Build restarts building
13:49 12-sept: linux & mac builds handed to QA
18:01 12-sept: signed-win32 build handed to QA
11:17 18-sept: QA signed off on all builds
00:01 19-sept: Build supposed to finish signing and publish builds externally
02:58 20-sept: files available externally for download
08:31 20-sept: mirror absorption completed and release announced

There were a few interesting point about this release
1) There was a 5.75 day delay between when the code freeze started, and when the tree was first deemed ready for builds to start.
2) After builds started, a last minute blocker bug caused those builds to be abandoned and new builds started. This respin cost Build 12 hours.
3) Between 13-17sept inclusive, both Build and QA switched to work on FF2.0.0.7 (a higher priority security firedrill release). This caused wall-clock delays.
4) After QA signoff, we delayed releasing Firefox3a8 from 18sept to 19sept, to avoid traffic load of releasing Firefox3a8 on the same day as Firefox2.0.0.7.
5) There was a 1 day delay between when QA signed off on the builds and when Build group ran the remaining manual steps (signing installer, pushing bits externally, etc). These remaining Build steps only took a handful of hours to complete. However, the person doing those remaining manual steps (ie me!), was sidetracked with other non-release work.