> Anybody here already using AMD64 chip on Linux distros (I'm currently > using FC3 and Gentoo)? Was the experience pleasant or frustrating? ;)
i've used gentoo on amd64 before and currently using it on openbsd. since the gentoo box is one of my developmental box before, i'd say i was impressed by noticeable increase in performance on pax-enabled kernel, and one of the good thing i like on amd64 is the page table nx bit w/c run obsd's w^x natively, without degrading performance. > Are there issues running 32-bit Linux applications on AMD64? How about > developing applications on various languages (Java, Python, Ruby, > C/C++)? amd64 has a legacy compatibility to 32-bit apps, and theoretically 32-bit apps should run on amd64. you can even have a 64-bit kernel running on top of a 32-bit environment. however, amd64 lacks proper segmentation but it should not be a major (or even minor) issue to most users. as for the compiler issue (this is c compiler specific), in order to fully access all of amd64's registers, you have to use new prefixes. this may be a bit disadvantage at first because traditionally. it is better to use the old register than to access and get a new one, but since compilers only use these prefixes when they just need it, imho it is more wise to use new register than to store the register in the memory and then reload it. this is specially true when you lack space in the old register. as for applications, there may be some minor issues. for example, a certain application was coded to run in 32-bit mode and does not really use amd64's larger address space and pointers, compiling them using a 64-bit compiler will not make them 64-bit applications for as long as the application code will not support the larger pointers offered by amd64, it will run the same as if it were compiled on a 32-bit environment. and if you're using a binary based distro, one disadvantage is that most of the major distro lacks support on pure amd64 packages. > > I'm currently evaluating if buying a AMD64-bit powered PC is a better > option than another usual 32-bit chip. Any constructive/non-bigot > tips, opinions & recommendations will be highly appreciated :) it has a bit disadvantage if you intend to run pure 32-bit applications. but if you want to access the full capability of 64-bit computing, then buying amd64 is worthy. it has a larger address space, a new set of instructions and registers and lastly the good NX bit :-) -- 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
