On Thu, Dec 20, 2007 at 08:24:12AM +0100, Roger Oberholtzer wrote: > On Wed, 2007-12-19 at 09:10 -0800, Greg KH wrote: > > On Wed, Dec 19, 2007 at 02:44:41PM +0100, Roger Oberholtzer wrote: > > > > > > I have installed the RT kernel on 10.3. Comes up as expected. I have yet > > > to see how it will effect my data gathering applications. > > > > Then don't use it :) > > I was unclear. I meant I had not evaluated it yet. In fact, we do things > like get kernel signals when a photocell triggers. We want them as soon > as possible, at least with a similar delay most times. We also receive > network packets from data collection devices. We control measurement > systems using real time DGPS locations, expecting good accuracy when the > system is moving at >90 km/h. All this should arrive is our application > in a decent predictable time. We run a mix of threads and SIGIO > handlers. All this is working within our currently stated limits. But, > as always, our users always like accuracy improvements. So, I am > evaluating the RT kernel to see what it may, or may not, offer in this.
Ok, that makes more sense, thanks for explaining it. > > Seriously, only use the -rt kernel if you _really_ know what you are > > wanting it for. It will cause your machine to run slower overall, which > > is probably not your intention... > > > > > I also have the nvidia driver installed via YaST. When I run the RT > > > kernel, of course the nvidia driver is not present. What is the best way > > > to sort this out? > > > > Don't use the -rt kernel, it will not work with the nvidia driver. > > OK. OOC, are any of the RT kernel optimizations in macros in include > files? Yes, some are. > Meaning the code must be compiled to take advantage? Kernel drivers must be re-compiled. > The normal X server is not recompiled to expect the RT kernel. That's because it is not a kernel driver, yet :) > Should there be similar issues with that as with the nvidia driver? Yes there will be. > Does this apply to vmware as well? Yes. _ANY_ kernel module will have to be recompiled to work properly with the -rt kernel, just like any other kernel version we provide. > > > Since I used YaST to install the nvidia driver, it > > > should get updated when there is a new kernel. I do not want to mess > > > that up to get it to work with the RT kernel variant. Should I just > > > re-install the nvidia driver when running the RT kernel? I guess the RT > > > kernel is a parallel kernel, not really a new kernel. > > > > What do you mean "new kernel"? It's just a different variant, one for a > > specific need. > > If I get a kernel update, the YaST-based nvidia install claims that it > will magically keep the nvidia driver working with each update. That's a pretty bold claim :) Anyway, as the nvidia driver is closed source, I really have no idea how it interacts with the kernel at all. Heck, the fact that it even works for anyone is amazing to me... > I do not need to take action. The RT kernel, I am guessing, is not > considered an update, which makes sense. That's right, it is just another kernel "variant" like the -bigsmp kernel is. Good luck, greg k-h -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
