Todd Lyons wrote: > Damian G wrote on Fri, Jul 26, 2002 at 08:42:24PM -0300 : > >>does anybody know if the final 9.0 release will include a preemptible kernel? >>i've heard great things about the pre-emptible patch for linux ... and i'm still > > > I don't know for certain that it will or will not, but I just looked > through the current Cooker kernel and I did not see the preemptible > patch applied. > > You do realize that using this patch pretty much prevents the machine > from being used as a high capacity server. It allow the kernel to be > pulled away from "unimportant" things to take care of "really important" > things like your desktop. Hardly an acceptable compromise on a server.
This is totally untrue. In fact the preemptive kernel has been added to the 2.5 series and will be in 2.6 because it results in better preformance and lower latency. Much of userspace is spent in kernel space getting IO done. A preemptive kernel allows any process to be interrupted even while in the kernel. For example, when X needs to draw some stuff to the video card, that is done at a lower level in the kernel. A non-premptive kernel would not be able to interupt the process while it was in kernel space. The preeptive kernel can. Example of fully premptive kernel: Solaris, among many others.... Some more stuff to read: http://www.linuxjournal.com/article.php?sid=5833 <- kernel locking http://vig.pearsoned.com/samplechapter/0130224960.pdf <- Sample chapter on Solaris Kernel internals http://www.tech9.net/rml/linux/ <- more links of how linux preemptive kernel works -- Bryan Whitehead SysAdmin - JPL - Interferometry Systems and Technology Phone: 818 354 2903 [EMAIL PROTECTED]
Want to buy your Pack or Services from MandrakeSoft? Go to http://www.mandrakestore.com
