4 Jan
2018
4 Jan
'18
10:10 p.m.
On 04/01/18 19:56, Paul Davis wrote:
On Thu, Jan 4, 2018 at 2:43 PM, Robin Gareus <robin(a)gareus.org
<mailto:robin@gareus.org>> wrote:
Depends on your DAW. In Ardour's case there is no context-switch. All
tracks, Busses and FX run in the same process. So there won't be any
direct effect.
Low-latency I/O however (soundcard) will see additional overhead, as
will JACK with multiple clients (one context switch per client).
is this correct? my impression is that KPTI makes user->kernel and
kernel->user switches more expensive tha they used to be, but does
not change the cost of a context switch that stays in the same ring mode.
so, basically, system calls cost more; context switches stay at about
the same cost.
https://lwn.net/Articles/741878/ - top-most page table is duplicated and
stripped of kernel pages; duplicate is active when running userspace.