I can't help you with PCI bandwidth usage(and personally I'd be very interested in being able to measure that), but I do know that Nehalem-based Intel Core i7s (and presumably more recent Intel CPUs) export PMCs for measuring memory bandwidth utilization. The PMCs for the Core i7 are:
QMC_BUSY.WRITE.CH0 QMC_BUSY.READ.CH0 QMC_BUSY.WRITE.CH1 QMC_BUSY.READ.CH1 QMC_BUSY.WRITE.CH2 QMC_BUSY.READ.CH2 You can divide these by UCLOCK to get the percent utilization. If you hate doing math by hand I've written a simple curses-based utility for measuring PMC statistics like this: https://code.google.com/p/perfdb/ It outputs stats like this: Memory Channel Utilization: (hotkey m) GQ_Write_Nonempty: 0.11 GQ_To_L3_Busy: 0.00 GQ_To_QPI_Busy: 0.00 GQ_To_Core_Busy: 0.00 Chan0_Util_Write: 0.01 Chan0_Util_Read: 0.03 Chan1_Util_Write: 0.00 Chan1_Util_Read: 0.03 Chan2_Util_Write: 0.00 Chan2_Util_Read: 0.00 It's still very much a work in progress and there's zero documentation for it(hint: the left and right arrow keys are used to cycle between pages of stats, and the q key quits) but I thought that I'd mention it. _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[email protected]"
