Blog 6

In your own words explain how linux kernels are numbered.

Geez, who’d a thunk it? Obviously, not me, I had no idea that so much could be written about the version numbering of an OS. I really don’t know that I can make this subject interesting or think of a new way to explain it. It seems an overdone subject to me. Here goes…

The first release of the Linux kernel was in September of 1991 as 0.01 by Linus Torvalds. In October, it went to version 0.02 and so on. In March 1994 they went to 1.0.

The numbering scheme currently consists of four numbers, like A.B.C.D and maybe some letters. Let's take Pandora’s revision number of 2.6.13-1.1532_FC4 and see if I can explain it.

The first number in the ‘A’ position is the kernel number. It rarely changes. That’s kind of obvious since current kernel is only at 2.b.c.d right now. That was easy.

The second number in the ‘B’ position is 6 for major kernel revisions. This position used to be an odd/even system. When the number was odd it was a developmental version. When the number was even it was a stable release. The problem with that system was that a lot of people did not want to put a developmental version on and risk losing their system or their data. So, when they did release the stable version more bugs would be found because of new scenario’s that did not get tested in the development phase. Now with the 2.6.x numbering scheme they have eliminated the odd/even system.

So, let’s look at the ‘C’ position, in Pandora’s case it is 13-1. This position was for minor revisions such as bug fixes, new drivers, features, and security patches. Back at release 2.6.8 there was a serious flaw that had to be fixed immediately and that gave us the ‘D’ postion. With revision 2.6.11 a new policy was implemented and bug fixes and security patches are now in the ‘D’ postion. The ‘C’ postion is now only for new drivers and features.

Pandora’s ‘D’ postion is 1532_FC4. The ‘D’ postion is also associated with the ‘build’ number. The build number is the number of times the compiler has built the kernel. So, I think, in Pandora’s case it would be 1532 times or 1532 bug fixes to the kernel. From what I can find out about the letters that are added in, those would be the developer’s initials. You could also, see ‘rc1’ or ‘rc2’ which stands for release candidate 1 or release candidate 2 instead of the developers initials. I think I got it.