Feature changed by: Dmitri Mittov (Michael_Knight) Feature #305694, revision 14 Title: Separate Desktop / Server Kernels openSUSE-11.2: Unconfirmed Priority Requester: Important Requested by: Dean Hilkewich (deanjo13) Partner organization: openSUSE.org Description: It seems to me that the current default kernels are somewhat hurting openSUSE's performance perception. Current kernel configs are OK but are not very well suited for desktop usage. In the future I would like to see a kernel package that is optimized for desktop usage. Current timer settings and no preemption really (sometimes drastically) hurts openGL performance and applications such as wine and causes alot of issues such as audio studdering. It would be nice to see a separate desktop performance kernel package with options such as Preemption model set to Preemptable Kenel (low-latency Desktop) and Timer Frequency Set to 1000 Hz, HPET support, Tickless System, disable optimize for size, disable Control Group support and disable Group CPU scheduler. You could also disable items and modules that are extremely rare in a desktop environment such as ATM support, Infiniband etc etc as these are not typically used in a desktop scenario which would be a large majority of openSUSE users. Further performance enhancements would also be done through out the system aimed at desktop use as well such as disabling barriers (even making it a simple checkmark option in the partitioner). Such optimizations for desktop usage can overcome openSUSE's reputation as being slower then the other mainstream distro's. The kernel settings alone can make up to a 30-40% increase in framerates in wine games for example and can cure alot of hiccups in multimedia apps. Discussion: #1: Bernhard Friedreich (bernhard1234) (2009-01-18 15:25:11) wow.. I didn't know about that facts.. I vote for that one! (running both a server and multiple notebooks on openSUSE) #2: Jan Engelhardt (jengelh) (2009-01-19 09:48:49) So why do not you use the RT kernel if your problems are that bad? Also, HPET and tickless is already enabled if you have not noticed. If you suggest disabling Optimize For Size, then I disclaim that you know all of the facts. A smaller kernel results in less instructions to fetch and run, and as such, less execution time to complete a given task. Unless you have specific numbers that an unloaded ATM module slows down your daily operations, it is not going to go away just because you think it is responsible for speed issues. Because as I read the source, it seems to me that it merely introduces one test and branch to the IPv4 ARP code, and that is just so small it is ridiculous to debate about. I do however, would want to see the kernel package being split up so as to have drivers that "probably are not" desktop- related in this decade, like ATM, in a separate installable package. #3: Dean Hilkewich (deanjo13) (2009-01-21 06:12:22) Yes I realize that HPET and tickless are already in there by default. I'm just pointing out settings that do make a difference for desktop use. Optimize for Size (=Os) can in theory reduce the executable size and can in some cases have small increases due to better cache usage, however in real life practice on a desktop you will find that disabling it (-02) does give a real life performance gain. Feel free to benchmark on your own as well (BTW Grub starts looking pretty squished with tones of kernels installed). These settings have been tested tried and true in the mailing lists, forums, etc. The RT kernel still defaults to a 250 Hz timer, Control Group support and Group CPU. All of these hurt multimedia and GL app performance. Easiest way of testing this for yourself is put a demanding game in wine such as command and conquer 3 in wine and play it or try to play high def content on a system with marginal system specs to do so. They make all the world of difference. The reason I recommended removing ATM, Infniband etc etc etc for the same reasons that you would like to see a separate kernel package for little if ever used anymore modules. I'm sure if you went through opensuse-help's own mailing list you can see these configs mentioned more then a few times and the results they give users afterwards. + #4: Dmitri Mittov (michael_knight) (2009-01-22 08:40:14) + How it will have impact to installation procces? Does user have to + choose kernel manually. Or it will be done automatically with help of + some criteria? -- openSUSE Feature: https://features.opensuse.org/?rm=feature_show&id=305694