Hi Ken, The short answer is depends heavily on your motherboard and the way you are getting the data.
For example, if you are doing it via Intel power node manager > /usr/sbin/ipmi-oem intelnm get-node-manager-statistics Current Power : 490 Watts Minimum Power : 36 Watts Maximum Power : 681 Watts Average Power : 497 Watts Power Statistics Reporting Period : 1 seconds <snip> I think the output speaks for itself, there is instantaneous and averages. If it's DCMI > /usr/sbin/ipmi-dcmi --get-system-power-statistics Current Power : 246 Watts Minimum Power over sampling duration : 246 watts Maximum Power over sampling duration : 246 watts Average Power over sampling duration : 246 watts Time Stamp : 05/15/2012 - 18:31:24 Statistics reporting time period : 69380 milliseconds Power Measurement : Not Available likewise instantaneous & averages. Here's a specific one to Dell > /usr/sbin/ipmi-oem dell get-power-consumption-data Cumulative Energy Start Time : 09/10/09 - 16:07:49 Cumulative Energy : 199.93 kWh Peak Amp Time : 04/27/11 - 19:18:27 Peak Amp : 0.90 A Peak Watt Time : 04/27/11 - 23:10:10 Peak Watt : 197 W It appears this is definitely an averaging one. If you are getting it via ipmi-sensors, it's almost definitely instantenous. Universally, I would say they are never blocking calls. The interval is usually read through another one of the options available in the tool/tools or listed right there (in several of the cases above). Don't remember options off the top of my head, but hopefully some trial & error with the options listed in the manpage will be enough. Hope that helps, Al On Mon, 2014-01-13 at 15:37 +0000, Ken O'Brien wrote: > Dear freeipmi devs, > > I would like to programmatically read power consumption using freeipmi. > I am wondering, how frequently can I poll using ipmi to read this value. > More so, how often is this value updated in hardware. Is it a blocking > call? > > The value returned is in units of watts. Is this an instantaneous value, > or the average value over a set interval? If an interval, how do I read > this interval. > > Best Regards, > > Ken > > > > > _______________________________________________ > Freeipmi-users mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/freeipmi-users -- Albert Chu [email protected] Computer Scientist High Performance Systems Division Lawrence Livermore National Laboratory _______________________________________________ Freeipmi-users mailing list [email protected] https://lists.gnu.org/mailman/listinfo/freeipmi-users
