> Subject: Re: jailhouse jitter? > > On 27.07.20 08:25, Peng Fan wrote: > > Hi Jan > > ... > > > > > I tested the SDEI on i.MX8MM, it shows the jitter became smaller. > > > > Without SDEI, the gic-demo jitter is 999ns+ With SDEI, the gic-demo > > jitter is 124ns~246ns. > > > > Indeed no more vmexits. > > > > But the max jitter, some times SDEI bigger only when program start up, > mostly because of CACHE WARM UP I think. > > That is one source. If you add a warm-up period, they can be mitigated, > though. > > The other source might be last-level cache sharing. If there are cache-miss > counters, maybe you can check if those increase along the peaks.
Yes. When I add stress-ng in root cell, the jitter became larger sometimes. > > > > > Will you move SDEI support to jailhouse mainline? > > Once the to-dos are addressed. Any contributions? I'll read more into your patches and check the to-dos you listed in the jailhouse commit log to see what I could help there. > > BTW, did you have to patch ATF for your experiment? Will you upstream that > patch? Yes. I'll upstream that. Quite simple, I only enabled one SDEI private event. Regards, Peng. > > Jan > > -- > Siemens AG, Corporate Technology, CT RDA IOT SES-DE Corporate > Competence Center Embedded Linux -- You received this message because you are subscribed to the Google Groups "Jailhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to jailhouse-dev+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/jailhouse-dev/DB6PR0402MB27609A148CE4F1B5DC105D3088720%40DB6PR0402MB2760.eurprd04.prod.outlook.com.
