Torvalds, who founded the Linux kernel project in the early 1990s, on Thursday finalised the 2.5.75 kernel, which he said would be the last in the series. The 2.5 kernel, a development project aimed at experimenting with new technologies, will be integrated into the 2.6 kernel for use in finished products.
The developer, who recently took a position with the Open Source Development Lab (OSDL), said that work on a test version of the 2.6 kernel would now begin. "This is the last 2.5.x kernel, so take note," he wrote on a kernel-development mailing list. Torvalds added that he and developer Andrew Morton "are going to start a 'pre-2.6' series where getting patches in is going to be a lot harder."
The 2.5.75 kernel integrates an "anticipatory scheduler" that has long been in development and includes updates for chip architectures from ARM and Intel, Torvalds said. The kernel will now go into maintenance mode, where active development cools off, and new features are unlikely to be introduced.
Torvalds missed a goal of releasing the 2.6 kernel in June, but the new test kernel could now arrive in a few days' time. This will be followed by a full release of the 2.6.0 kernel, which is unlikely to occur for a few months, Torvalds said. Once it arrives, it will probably be several more months before Linux vendors incorporate the kernel into their products.
IBM executives said in June that the company expected products using the 2.6 kernel to be released in the first half of 2004. Previously, they had hoped for the second half of 2003.
Linux, a Unix-like operating system collaboratively created by numerous programmers in the open-source movement, began as a hobby but now is used by many companies worldwide.
IBM, for example, said last week that financial services firm ING Canada bought an IBM z900 mainframe to run Linux applications. The system will be used to help process increasing amounts of insurance-claim transactions, the companies said.
