On Wed, 17 Aug 2005 18:10, Peter Williams wrote: > Michal Piotrowski wrote: > > Hi, > > here are schedulers benchmark (part2): > > [bits deleted] > > Here's a summary of your output generated using the attached Python script. > > | Build Statistics | Overall Statistics > > ----------------------------------------------------------------------- > Scheduler| Real CPU SYS TPT | CPU TPT delay CXSW > > | (secs) (secs) (%) (%) | (secs) (%) (secs) > > ----------------------------------------------------------------------- > ingosched| 3128.5 5056.3 8.18 161.6 | 5379.5 171.9 159367.4 1556452 > staircase| 3131.2 5032.6 8.09 160.7 | 5352.9 170.9 135193.0 1670366 > spa_no_frills| 3103.8 5049.5 7.98 162.7 | 5266.7 169.7 172384.8 520937 > zaphod(d,d)| 3561.7 4823.8 9.25 135.4 | 5132.0 144.1 148361.5 1771617 > zaphod(d,0)| 3551.2 4809.9 9.19 135.4 | 5114.7 144.0 144022.0 1784814 > zaphod(0,d)| 3126.8 5063.2 8.11 161.9 | 5278.1 168.8 173438.4 573587 > zaphod(0,0)| 3105.5 5052.9 7.98 162.7 | 5254.8 169.2 165774.4 577534 > nicksched| 3294.7 5095.1 9.10 154.6 | 5425.4 164.6 104298.2 2205665 > > where the (x,y) after zaphod means (max_ia_bonus, max_tpt_bonus) and "d" > means default. I had to kill a few significant digits to squeeze it > into 71 columns. Overall statistics are extracted from the schedstats > data. In the "Build Statistics" "CPU" is the sum of the user and sys > times and "SYS" is the percentage of that which was sys time (as I feel > that is a better thing to compare than raw sys times). > > I was intrigued by the fact that zaphod(d,d) and zaphod(d,0) take longer > in real time but use less cpu. I was assuming that this meant that some > other job was getting some cpu but the schedstats data doesn't support > that. Also it wouldn't make sense anyway as you'd expect jobs doing the > same amount of work to use roughly the same amount of cpu. My latest > theory is that your machine has hyper threads and this artifact is > caused by the mechanism in the scheduler for handling tasks with > differing priority in sibling hyper thread channels. Does your system > have hyper threads?
That would only do something if there was a difference in 'nice' levels. What you're seeing is the fact that balancing is intimately tied in with timeslice size and you have increased idle time. Cheers, Con - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
