Edward Shu wrote: > Randy Fishel: >> I am sponsoring this case for Rafael Vanoni and Aubrey Li. It proposes >> a kstat module for observing turbo mode on Intel processors. It proposes >> a micro/patch binding and a commited module. I believe that this case >> qualifies as a self-review, should someone request, it can be turned >> into a fasttrack. >> >> >> Template Version: @(#)sac_nextcase %I% %G% SMI >> This information is Copyright 2009 Sun Microsystems >> 1. Introduction >> 1.1. Project/Component Working Name: >> Turbo mode observability >> 1.2. Name of Document Author/Supplier: >> Author: Rafael Vanoni >> 1.3 Date of This Document: >> 12 February, 2009 >> 4. Technical Description >> This RFE proposes to integrate observability features for Intel's >> "Turbo Mode" feature. This functionality improves system performance >> by raising the operating frequency of a subset of the system's cores >> when at least half of the total amount of cores are idle and there's >> is thermal headroom to do so. >> > I think the transition is controlled by some firmware, and the OS can > only read the state instead of controlling this behavior. How often > does the OS read the register to refresh the kstats? >
Yes, the paragraph is describing the behavior of the feature, not implying that the OS controls it. The registers are read on demand by kstat or its consumers. Rafael
