On Wed, 2009-08-26 at 17:45 +0300, Maxim Levitsky wrote: > On Wed, 2009-08-26 at 09:47 -0400, Christoph Lameter wrote: > > On Wed, 26 Aug 2009, raz ben yehuda wrote: > > > > > How will the kernel is going to handle 32 processors machines ? These > > > numbers are no longer a science-fiction. > > > > The kernel is already running on 4096 processor machines. Dont worry about > > that. > > > > > What i am suggesting is merely a different approach of how to handle > > > multiple core systems. instead of thinking in processes, threads and so > > > on i am thinking in services. Why not take a processor and define this > > > processor to do just firewalling ? encryption ? routing ? transmission ? > > > video processing... and so on... > > > > I think that is a valuable avenue to explore. What we do so far is > > treating each processor equally. Dedicating a processor has benefits in > > terms of cache hotness and limits OS noise. > > > > Most of the large processor configurations already partition the system > > using cpusets in order to limit the disturbance by OS processing. A set of > > cpus is used for OS activities and system daemons are put into that set. > > But what can be done is limited because the OS threads as well as > > interrupt and timer processing etc cannot currently be moved. The ideas > > that you are proposing are particularly usedful for applications that > > require low latencies and cannot tolerate OS noise easily (Infiniband MPI > > base jobs f.e.) > > My 0.2 cents: > > I have always been fascinated by the idea of controlling another cpu > from the main CPU. > > Usually these cpus are custom, run proprietary software, and have no > datasheet on their I/O interfaces. > > But, being able to turn an ordinary CPU into something like that seems > to be very nice. > > For example, It might help with profiling. Think about a program that > can run uninterrupted how much it wants. > > I might even be better, if the dedicated CPU would use a predefined > reserved memory range (I wish there was a way to actually lock it to > that range) > > On the other hand, I could see this as a jump platform for more > proprietary code, something like that: we use linux in out server > platform, but out "insert buzzword here" network stack pro+ can handle > 100% more load that linux does, and it runs on a dedicated core.... > > In the other words, we might see 'firmwares' that take an entire cpu for > their usage. This is exactly what offsched (sos) is. you got it. SOS was partly inspired by the notion of a GPU. Processors are to become more and more redundant and Linux as an evolutionary system must use it. why not offload raid5 write engine ? why not encrypt in a different processor ? Also , having so many processors in a single OS means a bug prone system , with endless contention points when two or more OS processors interacts. let's make things simpler. > > > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
