To clarify, I am suggesting that the reported numbers are incorrect, not that there is some strange new loads going on.
I did many tests with disk I/O and CPU loading and such to determine if there were any real increased overheads. Maybe a couple of percent of CPU OS increased overhead and a little more on disk I/O. Also, and in case anyone is interested, I graphed all of this stuff over many hours and two kernels. see: http://ubuntuforums.org/showthread.php?t=2189769 the graphs are there. ** Attachment added: "The top info asked for." https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1254920/+attachment/3917148/+files/top.out -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1254920 Title: CPU utilization / accounting issues Status in “linux” package in Ubuntu: Incomplete Bug description: The issue is on a Trusty 32 bit server edition. It is the very very old computer that I use for minimum requirements testing. The issue is CPU user, sys, idle, and wait information makes absolutely no sense at all. For example with the commands "top" or "vmstat" I believe I have isolated the issue down to kernel configuration differences between Saucy and Trusty. I used the two otherwise same kernels from the ppa to come to this conclusion (after many many other kernels and such were tried). References: http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.12-saucy/ http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.12-trusty/ While there are a lot of configuration differences that are obviously not the issue (or so I think), there are many that I don't know if they could be or not. The computer I am using is too pathetic to compile the kernel (it takes 34 hours, and then it gives up before finishing anyhow). I will attach the config difference file in a moment. Automatic bug stuff has never worked for me on any of my computers, but I'll attach the other stuff asked for shortly. Example of expected vmstat output (server relatively idle): doug@test-smy:~/configs$ vmstat 20 procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 0 0 292 3952 4936 48668 0 0 247 5 265 151 14 7 77 2 1 0 292 3912 4944 48708 0 0 2 2 252 50 0 0 100 0 1 0 292 3912 4944 48708 0 0 0 0 252 47 0 0 100 0 0 0 292 3900 4952 48708 0 0 0 2 252 49 0 0 99 1 0 0 292 3900 4952 48708 0 0 0 1 252 51 0 0 100 0 0 0 292 2636 4960 49928 0 0 61 1 253 56 0 0 99 1 Example of vmstat output now (server idle): doug@test-smy:~$ vmstat 20 procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 0 0 5312 5544 3408 47900 8 22 1412 78 24253 4209 44 30 9 17 0 0 5312 5528 3416 47916 0 0 0 1 252 41 0 0 40 60 0 0 5312 5528 3416 47916 0 0 0 0 251 40 0 25 0 75 0 0 5312 5528 3416 47916 0 0 0 0 252 39 17 0 50 33 0 0 5312 5528 3416 47916 0 0 0 0 252 39 0 0 40 60 0 0 5312 5516 3424 47916 0 0 0 1 252 41 0 25 0 75 0 0 5312 5516 3424 47916 0 0 0 0 252 40 0 17 33 50 doug@test-smy:~$ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu Trusty Tahr (development branch) Release: 14.04 Codename: trusty doug@test-smy:~$ uname -a Linux test-smy 3.12.0-4-generic #10-Ubuntu SMP Thu Nov 21 22:11:22 UTC 2013 i686 i686 i686 GNU/Linux To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1254920/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
