Messages in this thread | | | Date | Tue, 19 Nov 2013 20:14:34 +0100 | From | Peter Zijlstra <> | Subject | Re: [GIT PULL] core kernel update |
| |
On Tue, Nov 19, 2013 at 08:09:04PM +0100, Ingo Molnar wrote: > The actual value of the limit - here's the on-stack cpumask sizes of > the candidate range: > > 128 CPUs: 16 byte cpumasks > 256 CPUs: 32 byte cpumasks > 512 CPUs: 64 byte cpumasks
So 512 / 64bytes is a single cacheline and feels like a nice cut-off before requiring an extra indirection and more cachelines.
64 bytes also doesn't sound _that_ big to have on-stack.
So I'd go for having the cut-off on >512, unless of course theres evidence 64bytes is already too much.
| |