Re: [PATCH v8 2/2] nohz: set isolcpus when nohz_full is set

2015-04-14 Thread Peter Zijlstra
On Tue, Apr 14, 2015 at 05:26:45PM +0200, Frederic Weisbecker wrote: > On Tue, Apr 14, 2015 at 11:17:55AM -0400, Chris Metcalf wrote: > > nohz_full is only useful with isolcpus also set, since otherwise the > > scheduler has to run periodically to try to determine whether to steal > > work from oth

Re: [PATCH v8 2/2] nohz: set isolcpus when nohz_full is set

2015-04-14 Thread Frederic Weisbecker
On Tue, Apr 14, 2015 at 11:17:55AM -0400, Chris Metcalf wrote: > nohz_full is only useful with isolcpus also set, since otherwise the > scheduler has to run periodically to try to determine whether to steal > work from other cores. > > Accordingly, when booting with nohz_full=xxx on the command li

[PATCH v8 2/2] nohz: set isolcpus when nohz_full is set

2015-04-14 Thread Chris Metcalf
nohz_full is only useful with isolcpus also set, since otherwise the scheduler has to run periodically to try to determine whether to steal work from other cores. Accordingly, when booting with nohz_full=xxx on the command line, we should act as if isolcpus=xxx was also set, and set (or extend) th