Conditional tracepoints

Posted Dec 2, 2010 3:58 UTC (Thu) by thedevil (guest, #32913)
Parent article: Conditional tracepoints

"Tracing those calls could create a stream of useless events which would have to be filtered out by PowerTop, causing PowerTop itself to require more power."

LOL! Thanks for this bit of typical LWN humor. Sometimes I think the Editor has been born on other shores where this gift is more common :)

Conditional tracepoints

Posted Dec 2, 2010 10:16 UTC (Thu) by mjthayer (guest, #39183) [Link]

> "Tracing those calls could create a stream of useless events which would have to be filtered out by PowerTop, causing PowerTop itself to require more power."

It does make me wonder why the filtering logic couldn't just be in PowerTop, as having the tracepoint on is clearly not the normal case. I assume that it would have generated enough extra work and really changed the systems power usage enough to make PowerTop's analysis harder.