Linux 7.4-rc1 Arrives After the Busiest Merge Window on Record

The first test release of Linux kernel 7.4, known as 7.4-rc1, is now available. According to LWN.net, it follows the largest merge window the kernel project has ever recorded. During that window, developers merged 18,591 non-merge changesets. That total sets a new record, and it comes close to the number of patches merged across the entire 7.3 development cycle, which was itself a record.

Some of these terms need explaining. A merge window is the period, usually about two weeks, at the start of each kernel cycle when maintainers submit their new features and larger changes to be pulled into the main source tree. A changeset is a single recorded change to the code. "Non-merge" means the count leaves out the bookkeeping commits created when separate lines of development are joined together, so it counts only actual changes to the code. An rc or "prepatch" is a release candidate: a testing build released before the final version.

What this means

LWN reports that 2,678 developers have contributed to 7.4 so far, and 625 of them are contributing to the kernel for the first time. The figures cover only the merge window, so both numbers may rise as the cycle continues.

The most notable point is how much work landed at once. A cycle normally accumulates its patches across several release candidates. In this case, the merge window alone nearly matched everything the 7.3 cycle delivered from start to finish. The new record arrives straight after the previous one, which shows the volume of change entering the kernel is still climbing.

LWN's short report does not break the total down by subsystem, employer or type of change. It says subscribers can find more detail on its KSDB page for 7.4. ITVedas has not reviewed that material, so this article does not cover what the new code contains.

The large group of newcomers also matters. A first-time contributor is someone whose work has never been merged into the kernel before. Having 625 of them in one merge window means many people are joining the project's developer community.

What you can do

• Treat rc1 as test software. A release candidate exists so problems can be found before the final release. It is not meant for production servers or for computers you depend on every day.
• Help test if you can. Developers and hobbyists with spare hardware or virtual machines can run the prepatch and report bugs. Broad testing is especially useful after a merge window this large.
• Stay on your distribution's kernel. Most users should keep the kernel their Linux distribution provides and wait until the vendor packages the finished release.
• Watch the cycle. If you maintain drivers, out-of-tree modules or systems that depend on kernel behaviour, check the coming release candidates for changes that could affect your code.

Testing of 7.4-rc1 is now under way, and the final release will show how well the kernel's review and testing process handled a record amount of new code.