I have ubuntu running on a multi-core CPU with 32 cores. When I check the cpu usage using top command, sometime it shows more than 100 %, like 340%, 650% etc. I did some investigation and found that its actually a sum of usages across different cores. For example if 1st cpu usages is 20% , 2nd is 30%, 3rd is 40% and remaining are 0% then ‘top’ shows 20+30+40=90%.
Its bit confusing and misleading. I believe the top command should display the CPU usages between 0 to 100 by calculating the usages across all the cores. In my example above, I would expect -(90*100)/3200 =2.8125% . Is this a bug with top command ? should it be considered as an enhancement for future releases? please advise
top
behavior, and it is probably too lte to change it. Nothing stops you from using another command with a different reporting convention however :)