While many Linux geeks were looking forward to USB 3.0 support and new Firewire drivers, kernel developers have also been working on improvements to desktop interactivity, particularly when the OS is under memory pressure.
Currently desktop software slows down when its path jumps to a part of the code that is not cached in memory and needs to be paged-in from disk. That can be caused by poor memory management that doesn't scale all that well in the desktop environment.
In Linux kernel version 2.6.31, developers have added some heuristics to make it much harder for 'mapped executable pages' to get moved out of the list of active pages.
Benchmarks on memory-constrained desktops show clock time and major page-faults reduced by 50 per cent, and memory reads from disk are reduced by about two-thirds.
According to Techworld, this means that X desktop responsiveness is doubled under high memory pressure. According to memory flushing benchmarks the number of major page-faults dropped from 50 to 3 during 10 per cent cache hot reads.
This coupled with kernel mode-setting support for ATI Radeon graphics cards will make the Linux 2.6.31 kernel a significant jump on the desktop.