Re: [PATCH v1.1] evtchn: add early-out to evtchn_move_pirqs()

2022-07-05 Thread Julien Grall
Hi Jan, On 05/07/2022 17:10, Jan Beulich wrote: On 26.04.2022 12:44, Julien Grall wrote: On 26/04/2022 11:33, Jan Beulich wrote: See the code comment. The higher the rate of vCPU-s migrating across pCPU-s, the less useful this attempted optimization actually is. With credit2 the migration rate

Re: [PATCH v1.1] evtchn: add early-out to evtchn_move_pirqs()

2022-07-05 Thread Jan Beulich
On 26.04.2022 12:44, Julien Grall wrote: > On 26/04/2022 11:33, Jan Beulich wrote: >> See the code comment. The higher the rate of vCPU-s migrating across >> pCPU-s, the less useful this attempted optimization actually is. With >> credit2 the migration rate looks to be unduly high even on mostly id

Re: [PATCH v1.1] evtchn: add early-out to evtchn_move_pirqs()

2022-04-26 Thread Julien Grall
Hi Jan, On 26/04/2022 11:33, Jan Beulich wrote: See the code comment. The higher the rate of vCPU-s migrating across pCPU-s, the less useful this attempted optimization actually is. With credit2 the migration rate looks to be unduly high even on mostly idle systems, and hence on large systems lo

[PATCH v1.1] evtchn: add early-out to evtchn_move_pirqs()

2022-04-26 Thread Jan Beulich
See the code comment. The higher the rate of vCPU-s migrating across pCPU-s, the less useful this attempted optimization actually is. With credit2 the migration rate looks to be unduly high even on mostly idle systems, and hence on large systems lock contention here isn't very difficult to observe