On Sun, 2005-04-10 at 01:16, Andy Sy wrote: > Pete Santiago wrote: > > >> You're right it shouldn't eat swap, only if the buffers/cache is > >> bigger than the total space by loaded apps and libraries. The 916k you > >> see there are probably least used pages downgraded to swap, which is a > >> good thing because it usually means that Linux is taking back physical > >> memory and is putting it into good use. > >> And of course Linux's VM is not perfect > > > It's not perfect, but it's better than M$'s. 2.6 kernel performs a lot > > better than the 2.4 kernel included with fedora 1. > > Any technical reasons as to how Linux's VM is superior to NT/XP's? > > I have heard a lot of complaints on kerneltrap.org about how 2.6's > default swap behaviour likes to move dormant pages out to disk quite > early on and this makes for a slow startup when you re-click, say, > a Mozilla window that you haven't touched in a long time. > > This actually reminds me a lot about Win XP behaviour I have observed > and leads me to believe that architects of both systems made similar > decisions. > > There are some solid technical arguments for this behaviour, but in > my own experience, I side more with the user experience arguments > _against_ such swappiness. > > With Linux, you can change /proc/swappiness to prevent this sort of > thing from happening at the cost of smaller disk caches. XP might > also have some hidden registry setting to deal with this. > >
I'm guessing that *most* VM implementations generally swaps out unused pages (standard LRU with optimizations). Generally this should be a *good thing* as it increases the overall responsiveness of those actively running applications. Desktop users usually don't feel the speed up benefit (everything's fast), but instead will feel a "slow down" when a minimized application is re-clicked. Perhaps each user needs a different /proc/swappiness factor, or some alternative kernel VM implementation (better if VMs are pluggable/modules[?]) that is geared towards desktop usage/responsiveness. -- Philippine Linux Users' Group (PLUG) Mailing List [email protected] (#PLUG @ irc.free.net.ph) Official Website: http://plug.linux.org.ph Searchable Archives: http://marc.free.net.ph . To leave, go to http://lists.q-linux.com/mailman/listinfo/plug . Are you a Linux newbie? To join the newbie list, go to http://lists.q-linux.com/mailman/listinfo/ph-linux-newbie
