In the PowerTOP repository, the probe that fires when (on x86) the halt (or mwait) instruction is invoked is "cstate_transition". That's appropriate for x86, but i'd like to come up with a probe name that would be appropriate across both SPARC and x86.
For sun4v we don't invoke a halt or suspend instruction natively, but we instead yield to the hypervisor. This would also be true for i86pv under Xen I would imagine. For sun4u, on the OPL platforms we invoke a "suspend" instruction. I don't know to what extent that is a power saving operation vs one for performance in the case where we are multi-stranded. Terry, do you have thoughts or suggestions here? Thanks, -Eric > >> I've filed: >> >> 6635705 static DTrace probe points for CPU power management state >> transitions >> >> I'll send out a webrev when it's implemented. DTrace probes can have a >> level of stability associated >> with them. I might propose that they be considered "unstable" to >> start, and then after we're convinced >> that the interface is correct and sufficient we can go through ARC to >> promote their stability. Does that >> seem reasonable? >> > Perfectly. > _______________________________________________ > tesla-dev mailing list > tesla-dev at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/tesla-dev >
