

1) What does mpstat show?

Currently mpstat shows per cpu information. %usr, %sys, %idl, maj & min faults, interupts, 
per cpu. It also shows context switches.

2) What is intr, inth, csw, icsw, etc.

cpuid - the id of the cpu as asigned by the bios and that which shows in /proc/cpuinfo. 

majf - major page faults

minf - minor page faults

xcal - inter processor cross calls

intr - interupts

ithr - interupts as threads ** on linux this is the same as intr

csw - context switches

icsw - involuntary context switches

migr - thread migrations

smtx - spins on mutexes lock not acquirecd on the first try

srw - spins on reads / writes

us - %cpu in user time

sy - %cpu spent in system time

wt - %cpu spent in wait 

idl - %cpu in idl time

3) Why does one (or more) of my cpu's show no major or minor faults, or not interupts?

mpstat assumes that cpu's are number 0, 1, 2, 3, etc. If they are not then the algorythm used here
fails. This was discoverd in version 0.0.4, and 0.0.5, and will be hopefully fixed in 0.0.6.

4) Why is intr and ithr now combined into one field?

unlike NT and Solaris, and most other operating systems, Linux does not distinguish completely between threads and process. A process in Linux is basically a thread that does not necessarily have shared memory. If you were to show a tree view of teh process (such as that of ktop) then you would see that all process are child process of a parent proces, or a child of the init process. In essance one can think of init as the main process, and all other process are threads of init.


