On 2/10/2019 11:04 PM, Mike Galbraith wrote:
On Sat, 2019-02-09 at 15:50 -0800, L A Walsh wrote:
On 2/6/2019 7:34 AM, Richard Brown wrote:
Hi all,
CONFIG_PREEMPT_NONE (as seen in SLE/Leap)
Really? the desktop distro Leap uses a config setting intended for servers and that is documented to give unreliable response time for interactive use?
Shrug. Yes, worst case latency is higher than alternative models, but general case latency is fine, as it must must be, else servers couldn't use PREEMPT_NONE to service human interfacing clients. PREEMPT_NONE is just one of three trade-offs, each of the three a mixed bag of strength and weakness.
-Mike
For a desktop user who might like to user their computer interactively and use it to play music or stream a video while they compile the kernel, which would be the recommended kernel model? As for using PREEMPT-NONE to service humans who in my parents generation used slide rules or an abacus, I'm sure tolerating delays under PREEMPT-NONE is hardly noticeable. But other people have a lower tolerance, to the point that anything over 100ms (full round trip) has people complaining about the slow ping times for a modern PvP game. In the same light, there would be a 'best' choice for someone recording live video needing a minimum of latency, and for computers run servicing storage or web requests or running as build machines 24/7, the most efficient kernel would also be a best choice. It really isn't based on averages over long periods, but in the case of real-time recording or needing fast response time having something set for no preemption isn't the best choice. That said -- if it is known something is causing worst case performance under PREEMPT_NONE, it should be fixed besides being run in a SW environment where it won't or can't show the bad behavior. -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org