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.
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? Meaning the code must be compiled to take advantage? The normal X server is not recompiled to expect the RT kernel. Should there be similar issues with that as with the nvidia driver? Does this apply to vmware as well?
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. I do not need to take action. The RT kernel, I am guessing, is not considered an update, which makes sense. But it is unclear if the nvidia driver would be installed in any booted kernel where it does not already exist, or only in certain classes of kernels (updates that replace the current kernel vs. a second kernel installed in a parallel fashion and selectable via the boot menu).
again, don't use the -rt kernel unless you really know why you want to use it, and how to use it.
I am not a newbie. I am only trying to see how SUSE expected all this to work, and what parts are not expected to be used with the RT kernel. Odd that SUSE would go through all the trouble to deliver the RT kernel, and then tell folk not to use it :) I do appreciate your warnings. All this is only a test to see if we can find improvements where we would like them, and of course, that there are no regressions elsewhere. All feedback welcome. Some even acted on :) -- Roger Oberholtzer OPQ Systems / Ramböll RST Ramböll Sverige AB Kapellgränd 7 P.O. Box 4205 SE-102 65 Stockholm, Sweden Office: Int +46 8-615 60 20 Mobile: Int +46 70-815 1696 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org