Messages in this thread |  | | From | safemode <> | Subject | Re: graphical swap comparison of aa and rik vm | Date | Thu, 1 Nov 2001 01:41:31 -0500 |
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On Thursday 01 November 2001 01:23, Mark Hahn wrote: > > Here is the graph http://safemode.homeip.net/vm_swapcomparison.png . > > It's > > here's my munge of the same data: > http://mhahn.mcmaster.ca/~hahn/foo.png > the measures I find interesting are the SI/SO rates. first, the most > obvious feature is that Rik-VM has a serious problem knowing when to *stop* > swapping out. but SO isn't a bad thing unless it's obsessive: it's when > you see high *swap-in* that you know the VM has previously chosen bad pages > to SO. and this is the second big difference: Rik-VM doesn't make nearly as > many mistakes - especially look at Andrea-VM thrashing out-in-out at ~ > samples 26-32. > > also, if you merely sum the SI and SO columns for each: > sum(SI) sum(SO) sum(SI+SO) > Rik-VM 43564 317448 290032 > AA-VM 118284 171748 361012 > to me, this looks like the same point: Rik being SO-happy, > Andrea having to SI a lot more. interesting also that Andrea wins the > race, in spite of poorer SO choices and more swap traffic overall. > > > Neadless to say that while running the test on either box, the entire > > computer became unresponsive multiple times for extended lengths of > > times. > > yes, unfortunately this corrupts the value of the data, since the > timecourses are not really comparable, and samples are only vaguely related > to time...
If you miss anything you miss the plateu data that would be found when the IO peaks. But i doubt much at all was really lost in this case. > regards, mark hahn.
Actually i found that most if not all of the vmstat's that weren't being displayed were displayed immediately after the "locks", ie. I got flooded with vmstats upon the computer becoming responsive again. Of course I should have been timing each run with a stopwatch, but that never crossed my mind that the vmstat would be lost. In other words i thought of it as analogous to having burst-lag on irc. Guess that's for tomorrow after work. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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