Hi Dan, Just now catching up on a pile of mail from the last week, so some of this will likely be out of order, but I really wanted to chime in here. On Thu, 2007-10-05 at 23:48 -0700, Dan Kohn wrote: > On May 10, 2007, at 11:28 PM, Takashi Ikebe wrote: > > > I agree that. > > Basically CGL is the Linux that applicable on carrier equipment. > > This means the CGL is different from general purpose Linux. > > Network equipment typically requires high availability, real time > > capability (response time), serviceability than scalability and > > total throughput. > > I think general purpose computing prefer latter. > > Therefore I think the acceptance of community is hard because of > > carrier specific functionality. and that's why CGL exists. [...] > I would appreciate if you could provide some specific examples > (perhaps from the CGL 4.0 spec) of NTT requirements whose > implementations were explicitly rejected by the kernel community. I think one of the things we want to keep in mind when we're talking about CG requirements and whether they've been accepted into mainline or not is that very few things are completely static in the kernel. An excellent example of this that I've been following closely over the past couple of years has been the work by Con Klovias and more recently Ingo Molnar on different schedulers. Real time behaviour has already been mentioned on the list (by at Takashi for sure and I think others as well) and a related part of that is scheduler fairness. Con's changes were rejected several times and now it looks likely that at least some version of his work will find its way into mainline. One of the jobs of the CGL working group, in my eyes, is to be a forum for discussing and coming to some sort of consensus on what features are important to carriers, then representing those interests to the mainline developers. It's entirely possible that something that is important to carriers may be diametrically opposed to something that is important to desktop or data centre or mobile interests and would be rejected by Linus et. al. until they are convinced of the merit of the feature in question. I think the new state of the world, with CGL and LSB and key kernel developers all under the same virtual roof we have a great opportunity for more effective communication than ever before and we should be looking at CGL P1s (which were frequently nominated or supported as P1s by SCOPE) which are not in mainline and determining how the PoCs can be tweaked (or retooled or completely redesigned) in a way that will make them acceptable. > I am suggesting, however, a change in focus in CGL toward specifying > requirements (what and why) and away from specifying > implementations. Further, I believe it is in the entire Linux > community's interest to avoid a fork. I completely agree that a fork would serve no one's purpose, but with the 4.0 specification we adopted a philosophy that it was reasonable (and even necessary in some cases) to have a P1 with an implementation that was outside mainline. We rejected any P1, however, which wasn't already in mainline or didn't have a reasonably well-maintained patch set against a modern kernel. I think that still fits with your suggestion that we focus on requirements more than implementations, but I think it's clear that in considering what level of priority to apply to a requirement, it's critical to consider possible implementations. -- Joe MacDonald <joe.macdonald@xxxxxxxxxxxxx> Wind River Systems -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 189 bytes Desc: This is a digitally signed message part Url : https://lists.linux-foundation.org/mailman/private/lf_carrier/attachments/20070515/a156ecfb/attachment.pgp