Hello Elie, On Tue, Feb 7, 2012 at 8:48 PM, Elie De Brauwer <eliedebrauwer@xxxxxxxxx> wrote: > Hello all, > > I've got a small suggestion related to man 5 proc ( > http://www.kernel.org/doc/man-pages/online/pages/man5/proc.5.html ). > If you go to /proc/loadavg it states > > <quote> > The fourth field consists of two numbers separated by a slash (/). > The first of these is the number of currently executing kernel > scheduling entities (processes, threads); this will be less than or > equal to the number of CPUs. The value after the slash is the number > of kernel scheduling entities that currently exist on the system. > </quote> > > When I take a look at /proc/loadavg this seems to make sense: > > edb@lapedb:~$ cat /proc/loadavg > 0.04 0.65 0.59 1/284 8102 > > However, suppose I run 4 background jobs of 'yes bla > /dev/null &' > > edb@lapedb:~$ yes bla > /dev/null & > [1] 8111 > edb@lapedb:~$ yes bla > /dev/null & > [2] 8112 > edb@lapedb:~$ yes bla > /dev/null & > [3] 8113 > edb@lapedb:~$ yes bla > /dev/null & > [4] 8114 > edb@lapedb:~$ cat /proc/loadavg > 0.18 0.59 0.57 5/289 8115 > edb@lapedb:~$ cat /proc/cpuinfo | grep processor > processor : 0 > processor : 1 > > Then I see that the 'fourth field' before the slash is five, whereas > the number of cpu's (dual core laptop) is only two. Hence the 'this > will be less than or equal to the number of CPUs' in the manpage is > not correct. Now if we take a deeper look at how this /proc/loadavg > gets created (in fs/proc/loadavg.c): > http://lxr.linux.no/#linux+v3.0.4/fs/proc/loadavg.c#L23 > > We can see that the fourth value before the fraction is the result of > 'nr_running()' which is turn lives in kern/sched.c (ref: > http://lxr.linux.no/#linux+v3.0.4/kernel/sched.c#L3197 ) and this > function just counts the number of runnable threads for each of the > online cpu's. I have attached a path which rephrases this, the patch > is rather trivial. Thanks. I've applied this for man-pages-3.36. Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Author of "The Linux Programming Interface"; http://man7.org/tlpi/ -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
