I had this idea that I was going to implement in uperf. We provide a "statistics" flowop with various options for collecting different kinds of data. This way the user can specify what they need collected (and what penalty they are willing to pay). You could probably have a "stats-start" and 'stats-print'. Just a thought -neel
On Fri, May 30, 2008 at 10:35 AM -0700, eric kustarz wrote: > > On May 30, 2008, at 7:56 AM, Sean McGrath - Sun Microsystems Ireland > wrote: > > > eric kustarz stated: > > < > > > < > Currently both tools gives different view of io. While filebench > > < > simulates real workload, it cannot show what vdbench shows. > > < > E.g. we were doing some hardware array tests and it turned out > > (using > > < > vdbench) that the array works in a really strange way: sometimes > > its > > < > IOPS jumps very high, sometimes it lows very much. There were > > < > a few other tests where vdbench shows how IOPS behaves in each > > < > second of workload. I am affraid filebench _currently_ cannot > > give us > > < > the same data. > > < > > < Good point. > > < > > < We actually have this via Xanadu, though i just tried it and it > > looks > > < like Xanadu is not working. > > < > > < Also, at the UCSC benchmarking conference last monday we kicked > > around > > < the idea of showing a distribution of results instead of just > > averages. > > > > Yes, averages tell only part of the story. > > Agreed. > > > > > > > as an example, libmicro has some nice statistics that it gives with > > its metric > > results. Could the methods be used within filebench ? > > Possibly, its something we're discussing so we'll take input (like > yours)... > > I like the distribution output (perhaps similar to Dtrace's quantize) > better though. > > eric > > > > > > > eg: > > > > # STATISTICS usecs/call (raw) usecs/call (outliers > > removed) > > # min 0.00448 0.00448 > > # max 0.00623 0.00459 > > # mean 0.00453 0.00451 > > # median 0.00453 0.00453 > > # stddev 0.00013 0.00003 > > # standard error 0.00001 0.00000 > > # 99% confidence level 0.00002 0.00000 > > # skew 11.81224 0.45940 > > # kurtosis 153.61917 -0.55683 > > # time correlation -0.00000 -0.00000 > > # > > # elasped time 0.01943 > > # number of samples 196 > > # number of outliers 6 > > # getnsecs overhead 288 > > > > < > > < eric > > < _______________________________________________ > > < perf-discuss mailing list > > < perf-discuss@opensolaris.org > > > > -- > > Sean. > > . > > _______________________________________________ > perf-discuss mailing list > perf-discuss@opensolaris.org -- --- Neelakanth Nadgir http://blogs.sun.com/realneel _______________________________________________ perf-discuss mailing list perf-discuss@opensolaris.org