In a couple of earlier articles, we walked through the process of upgrading to the 2.6.0-test4 kernel [story], and then using a small patch to upgrade to the 2.6.0-test5 kernel [story]. Today we'll continue our patching efforts to upgrade to an even faster feeling and more stable kernel with Andrew Morton's [interview] -mm patchset [forum].
Andrew Morton began releasing his -mm kernel patches a little over a year ago, in the summer of 2002. The -mm tree began as a 90k patch against the 2.5.17 development kernel, merging in the remote kernel debugger, kgdb. By the release of 2.5.18, the -mm patchset had grown to nearly 238k, merging in a wide assortment of fixes and new functionality. As of this writing, the current -mm patchset is 2.6.0-test5-mm3, weighing in at nearly 5 megabytes. Andrew's -mm tree has evolved from a testing ground for numerous new technologies, to a comprehensive patchset that is usually more stable than the mainline 2.6.0-test kernel itself. This bodes well for the future of the 2.6 kernel, as Andrew Morton will soon be the official 2.6 kernel maintainer.
There are numerous reasons you may desire trying Andrew's -mm kernel tree. Stability alone is a good incentive, and scanning the lengthy changelog you'll find a significant number of bug fixes that have been applied. I asked Andrew how the stability of his kernel compares to that of the mainline 2.6.0-test kernel, and he replied that though occasionally new bugs creep in, due to having the latest fixes the -mm tree is generally more stable and up-to-date.