Ingo Molnar [interview] reviewed Con Kolivas [interview]'s swap-prefetching patches [story] suggesting that they were ready for inclusion in the mainline kernel, "I've reviewed it once again and in the !CONFIG_SWAP_PREFETCH case it's a clear NOP, while in the CONFIG_SWAP_PREFETCH=y case all the feedback i've seen so far was positive. Time to have this upstream and time for a desktop-oriented distro to pick it up." He went on to describe swap prefetch, "to the desktop user this is a speculative performance feature that he is willing to potentially waste CPU and IO capacity, in expectation of better performance. On the conceptual level it is _precisely the same thing as regular file readahead_. (with the difference that to me swapahead seems to be quite a bit more intelligent than our current file readahead logic.)"

Nick Piggin [interview] expressed some concern that the impact of the code still wasn't understood well enough, "I wanted to see some basic regression tests to show that it hasn't caused obvious problems, and some basic scenarios where it helps, so that we can analyze them. It is really simple, but I haven't got any since first asking." Ingo noted that the patch has generated a lot of positive feedback from users and it would be best to merge it into the kernel, going on to suggest that it would be good to get more people actively involved, "really, we are likely be better off by risking the merge of _bad_ code (which in the swap-prefetch case is the exact opposite of the truth), than to let code stagnate. People are clearly unhappy about certain desktop aspects of swapping, and the only way out of that is to let more people hack that code. Merging code involves more people. It will cause 'noise' and could cause regressions, but at least in this case the only impact is 'performance' and the feature is trivial to disable."