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Shashi Guruprasad authored
that although appeared to be right was actually causing errors to be accumalated. This fixes the high error rates in the bandwidth and loss rate numbers reported in OSDI. There are also code optimizations after profiling it that reduces the RTSched overhead. Another source of error was send/consume/request/reply which used to be given a very rough estimate of the CPU speed (600 instead of 601.37 Mhz for example). The latter comes from the boot up calibration in FreeBSD which is supposed to be accurate up to 10 microsecs on a 486. Using 600 instead of 601.37 causes an error of 0.22 % in the measurement. That is about 1.3 ms for an RTT of 600 ms. This error is worse when send/consume are used to calculate throughputs. The longer the period of measurement, the worse it becomes. I have committed changes in them as well. Defining the macro CPU_SPEED_IN_KHZ will get you kernels that take CPU_SPEED parameters in Khz instead of Mhz. So, you can specify 851940 instead of 850 for a pc850. boss:/tftpboot/x86/{send,consume,request,reply}.cpuinkhz lets you specify CPU_SPEED in Khz
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