Messages in this thread | | | Date | Mon, 13 Dec 2010 11:20:55 -0700 | From | "David S. Ahern" <> | Subject | Re: [PATCH 1/2] perf tools: Add reference timestamp to perf header |
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On 12/13/10 11:06, Peter Zijlstra wrote: > On Mon, 2010-12-13 at 11:01 -0700, David S. Ahern wrote: >>> Another problem with this approach is things like flight-recorder mode >>> where you constantly over-write your old data, you'd have to build some >>> trigger to always output a new record before you over-write the old one, >>> so there's always one consistent record around. Drift is an even more >>> serious problem here since flight-record more could be running for days >>> before (if ever) you dump it. >> >> Ok. I was not aware flight-recorder mode was an option today. > > You get it when you mmap the fd RO -- the only thing is you don't get a > consistent tail pointer so you have to fudge a bit.
Awesome. Flight recorder mode is on our wish list. I'll try it out when I get some time.
David
> > But even if we didn't have it, we'd need a solution that would work once > we did grow it ;-)
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