Ashok Raj wrote:
> On Wed, May 10, 2006 at 11:06:06PM -0700, Andrew Morton wrote:
> Hi Andrew,
>
> > Shaohua Li <[email protected]> wrote:
> > >
> > > CPU hotremove will migrate tasks and redirect interrupts off dead cpu.
> >
> > This seems an awful lot of code for something which happens so infrequently.
> >
> > How big is the problem you're fixing here, and what are the
> > user-observeable effects of these changes?
>
> This is useful when say a NUMA node is being removed. With new multi-core
> CPUs comming up, considering a 2 core with HT, we could have up to 4 logical
> per socket. On NUMA node with 4 sockets, a node removal will mean we
> do 16 single cpu offlines. Each time the process and interrupts could
> end up on a CPU that might be removed just immediatly.
But offlining all the cpus in a node is already something that just
works. If the user is all that concerned about not thrashing the
tasks running on that node, they would have a workload manager that
migrates the tasks off the node before shooting down cpus. Similar
argument applies to interrupt affinity.
I really haven't seen a compelling argument for why this is needed,
just a bunch of handwaving so far, sorry.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]