On Wed, Sep 05, 2007 at 08:25:54PM EDT, Karl. wrote: > On Wed, Sep 05, 2007 at 04:47:01PM -0400, cga2000 wrote: > > I updated my website a bit and put the whole lua script online, just in > case you feel like seeing it more in context. > http://mowson.org/karl/articles/dwm/
Not a bad script, but I prefer the cat! > > If you sample CPU activity every second and find process A used the > > CPU .02 seconds and process B .01 second and nothing else was > > dispatched during that time frame .. that would add up to 3% CPU .. > > with the CPU idle 97% of the time. > > Seems reasonable. Of course there will be buckets of background > processes using cpu time as well as what I assume are your foreground A > + B. Note that ideally you need to calculate time elapsed between > samples (as my script does) in case the scheduling of your sampling is > not exactly every 1s, otherwise you may find yourself going over 100% > apparent usage... Sure, the above was not meant to be a real-life situation. Just trying to prove to myself I understand the concept. > You can also look at /proc/loadavg for cpu usage info, but I find that > it doesn't tell me what I really want to know. My primary interest in > load is for those times when the computer seems to be unresponsive and I > want to know if it is cpu-bound or i/o-bound or whatever. In which > case, a 1-minute average is of no use. > > In case you haven't noticed, 'man proc' tells you much about what you > can find in the proc filesystem. (you can read the manpage online: > http://www.linuxmanpages.com/man5/proc.5.php) Thank you! > > Not sure why my "ps" + "add up what's in the %CPU column" does not > > give me the same results as the usual suspects, though. > > Are you including *all* processes in your ps? Don't forget rounding > errors too. Moot point, since I was unable to combine screen's backtick with a pipe. In any event, it was a _lot_ more fun doing it in awk :-( :-( :-( Anyway for those still holding their breath, this is what I came up with: backtick 3 0 0 awk 'BEGIN {file = "/proc/stat"; \ while (a==a) \ {getline < file;u=$2-up;s=$3-sp;n=$4-np;i=$5-ip; \ printf ("CPU: %2.1f\n"),(u+s)/(u+s+n+i)*100; \ up=$2;sp=$3;np=$4;ip=$5; \ close(file);system("sleep 1")}}' Removing the backslashes and joining the above 6 lines should give you back the original. I haven't been able to figure out how to split lines in a .screenrc. Notes: This one-liner reads /proc/stat/'s first line every second, computes the delta between successive values of $2-$5 and prints: (duser+dsystem) / (duser+dsystem+dnice+didle) * 100 .. where duser, etc.. are the user delta .. etc. Since your web site suggests you know a bit more about monitoring the system :-) !!! .. I would appreciate if you could confirm my algorithm is correct. I ran it next to conky in different windows and despite the fact I couldn't control the separate sampling I had a distinct feeling they were giving roughly the same results. One minor annoyance is that I haven't found a simple way to make the display of my %2.1f CPU percentage add a leading white space when the result of my calculation is < 10.0 .. and this makes my display jump about every once in a while. Guess I need to grab the "C" language printf man page. This is so distracting that if I can't find a way round this rapidly, I'll just test whether the result is < 10.0 and add an intervening' print " ". > > > A completely different approach, which I used briefly but abandoned > > > for various reasons, is to run conky in stdout mode. In this mode > > > you can set up all sorts of status monitors and have it spit them > > > out on stdout, ready to be piped into something. > > > > Not familiar with this mode. > > > > OTOH, the reason I'm adding some monitoring to screen is that I'm > > dumping conky .. the overhead mostly. So .. > > Same here. Conky is pretty, but if you're only using it to output text, > and not pretty graphics, then other tools start to become more > attractive. I was mostly using PII-400 machines, in which processing > power is best not squandered. Even on a PIII-650 it was so "active" that on my idle laptop it ended up monitoring itself and driving up my CPU's temperature to 70C+! Shades of Werner Heisenberg? cga _______________________________________________ screen-users mailing list screen-users@gnu.org http://lists.gnu.org/mailman/listinfo/screen-users
