On Thu, 23 Mar 2006, Alex Izvorski wrote: > Also the cpu load is measured with Andrew Morton's cyclesoak > tool which I believe to be quite accurate. there's something cyclesoak does which i'm not sure i agree with: cyclesoak process dirties an array of 1000000 bytes... so what you're really getting is some sort of composite measurement of memory system utilisation and cpu cycle availability. i think that 1MB number was chosen before 1MiB caches were common... and what you get during calibration is a L2 cache-hot loop, but i'm not sure that's an important number. i'd look at what happens if you increase cyclesoak.c busyloop_size to 8MB ... and decrease it to 128. the two extremes are going to weight the "cpu load" towards measuring available memory system bandwidth and available cpu cycles. also for calibration consider using a larger "-p n" ... especially if you've got any cpufreq/powernowd setup which is varying your clock rates... you want to be sure that it's calibrated (and measured) at a fixed clock rate. -dean - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
