Messages in this thread | | | Date | Wed, 1 Jul 2015 19:18:38 -0700 | From | "Paul E. McKenney" <> | Subject | Re: [PATCH RFC tip/core/rcu 0/5] Expedited grace periods encouraging normal ones |
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On Thu, Jul 02, 2015 at 03:59:55AM +0200, Mike Galbraith wrote: > On Wed, 2015-07-01 at 18:34 -0700, josh@joshtriplett.org wrote: > > On Thu, Jul 02, 2015 at 03:11:24AM +0200, Mike Galbraith wrote: > > > On Wed, 2015-07-01 at 09:17 -0700, Paul E. McKenney wrote: > > > > On Wed, Jul 01, 2015 at 04:17:10PM +0200, Peter Zijlstra wrote: > > > > > On Wed, Jul 01, 2015 at 07:00:31AM -0700, Paul E. McKenney wrote: > > > > > > > > > > > That is a bit extreme, Peter. > > > > > > > > > > Of course; but I'm really not seeing people taking due care with them > > > > > > > > ;-) > > > > > > > > > > Are a huge pile of them coming in this merge window or something? > > > > > > What raised your concerns on this issue? > > > > > > > > > > This is complete horse manure (breaking the nvidiot binary blob is a > > > > > good thing): > > > > > > > > > > 74b51ee152b6 ("ACPI / osl: speedup grace period in acpi_os_map_cleanup") > > > > > > > > Really??? > > > > > > > > I am not concerned about this one. After all, one of the first things > > > > that people do for OS-jitter-sensitive workloads is to get rid of > > > > binary blobs. > > > > > > I know two users who have no choice but to use the nvidia driver with > > > their realtime applications, as nouveau is not up to the task. > > > > Sounds like they have a relatively loose definition of "realtime", then. > > It would be better it they broke their beasts up into a bunch of small > synchronized boxen, but they use big boxen here and now, with realtime > rendering being a non-disposable portion of the load.
Does their normal workload trigger the condition that results in the expedited grace period? If so, do they use NO_HZ_FULL? (I am guessing "no".) If not, is the resulting double-context-switch on their worker CPUs a real problem for them? (I am guessing "no" given that they have not complained, at least not that I know of.)
Thanx, Paul
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