processes
Dave Krebes
My understanding of "process" is that the CPU of a personal computer cycles
through a set of tasks called "processes". There are typically 50-100 of
these. One process may monitor input from the keyboard, another to convert
data to a certain protocol, another to update the clock, etc. The CPU
performs a single calculation for a specific process and then moves on to
the next process. The instructions for this calculation are fed to the CPU
from the RAM (or cache?) The speed of the CPU, in Hertz, is the number of
such visits (calculations) the CPU performs in one second. So if there are
100 processes and the speed of the CPU is 1 GHz, then the CPU will perform a
calculation for a given process 10M times per second. The CPU needs to
"flush itself out" after each calculation (due to some sort of lingering
electromagnetic field?) and this, not the speed of electricity, is the
limiting factor in the speed of a CPU, and in turn the main factor in the
speed of the computer.
Is this right? And what is in the "proc" directory?
Ivan Marsh
What platform are you referring to CISC, RISC...
Do your own homework.
--
"All right, all right, if it will make you happy, I will overthrow society."
- Philip J. Fry
Whiskers
> Is the term "process" used in more than one sense in the IT world?
>
> My understanding of "process" is that the CPU of a personal computer cycles
> through a set of tasks called "processes". There are typically 50-100 of
> these.
[...]
> Is this right?
Not exactly. My laptop seems to be running many thousand processes right
now; two of them are the editor I'm typing into right now and the terminal
emulator that editor is running in ... PIDs 15450 and 15398 respectively.
> And what is in the "proc" directory?
Why not take a look?
--
-- ^^^^^^^^^^
-- Whiskers
-- ~~~~~~~~~~
John Hasler
> My laptop seems to be running many thousand processes right now...
Not likely.
> ...two of them are the editor I'm typing into right now and the
> terminal emulator that editor is running in ... PIDs 15450 and 15398
> respectively.
Every time a new process is started it gets the next higher PID. PIDs
are not reused until the counter wraps around. Try "ps a | wc -l".
--
John Hasler
jha...@newsguy.com
Dancing Horse Hill
Elmwood, WI USA
Dan C
> Is the term "process" used in more than one sense in the IT world?
<SNIP>
Bugger off, Win-droid, and do your own homework. Then, go update your
viruses like a good little Win-punk. Then, fuck off.
--
"Ubuntu" -- an African word, meaning "Slackware is too hard for me".
"Bother!" said Pooh, as he strafed the lifeboats.
Usenet Improvement Project: http://twovoyagers.com/improve-usenet.org/
Thanks, Obama: http://brandybuck.site40.net/pics/politica/thanks.jpg
Aragorn
as Dan C wrote...
> On Wed, 17 Feb 2010 21:45:35 +0000, Dave Krebes wrote:
>
>> Is the term "process" used in more than one sense in the IT world?
>
> <SNIP>
>
> Bugger off, Win-droid, and do your own homework. Then, go update your
> viruses like a good little Win-punk. Then, fuck off.
Oh, come on Dan, don't hold back. Tell us how you *really* feel...
<LOL>
--
*Aragorn*
(registered GNU/Linux user #223157)
SM
> In <3sZen.66141$Db2.22198@edtnps83>, on Wed, 17 Feb 2010 21:45:35 GMT,
> Different on every system. To see what's in yours...
>
> $ cd /proc
> $ ls -l
>
Unnecessary use of cd ;)
--
kasmra
:wq
Loki Harfagr
maybe not, imagine you're not looking what you think you're looking at, e-g:
$ cd /
$ mkdir -p PROc/{a,b,c,d}
$ ln -s PROc PROC
$ ls -l PROC
$ cd PROC && $ ls -l
Robert Newson
$ ls -l /proc
no need to cd at all ;)
J G Miller
> And what is in the "proc" directory?
Nothing until you actually go and look in it.
SM
> In <slrnhnputs...@ananas.Sauna>, on Thu, 18 Feb 2010 08:35:09 GMT,
> I think it's necessary to tailor the answer to the
> student. Given the nature of the question, I would
> suppose student might do
> $ ls -l /proc
> and, seeing subdirectories, he might then attempt
> $ ls -l sub or
> $ ls -l /sub both of which would naturally fail.
Sure but what's the harm in failing? After failing a couple of times
he/she might eventually learn it. It's better than developing a bad
habit of first cd'ing into a directory and then listing the contents.
> If the first instruction is 'cd /proc', those two
> probable failure modes are eliminated... though
> admittedly, nothing is absolutely idiot proof. ;-)
That's for sure.
--
kasmra
:wq
Jasen Betts
Baron
A process, is a recipe for doing something from beginning to end !
--
Best Regards:
Baron.
Baron
> In <slrnhnputs...@ananas.Sauna>, on Thu, 18 Feb 2010 08:35:09
> GMT, SM, kas...@ne-spamon.gmail.com wrote:
>> 2010-02-18, Steve Ackman skribis:
>
>>> Different on every system. To see what's in yours...
>>>
>>> $ cd /proc
>>> $ ls -l
>>>
>>
>> Unnecessary use of cd ;)
>
> I think it's necessary to tailor the answer to the
> student. Given the nature of the question, I would
> suppose student might do
> $ ls -l /proc
> and, seeing subdirectories, he might then attempt
> $ ls -l sub or
> $ ls -l /sub both of which would naturally fail.
>
> If the first instruction is 'cd /proc', those two
> probable failure modes are eliminated... though
> admittedly, nothing is absolutely idiot proof. ;-)
Particularly if they don't understand a process in the first place !
--
Best Regards:
Baron.
Jasen Betts
no that's an algorithm (or if suficciently detailed a program)
a process is the act of doing it.
Baron
Jason.
Yes, you're right. I should have realised when I posted.
Thanks for correcting my error.
--
Best Regards:
Baron.
Patrick Schueller
"Schrödinger's directory"?
http://en.wikipedia.org/wiki/Schr%C3%B6dinger%27s_cat
scnr, Patrick
--
OS: Ubuntu 9.10 · Kernel: 2.6.31-20-generic · KDE: 4.4.00 (KDE 4.4.0)
CPU: AMD Turion(tm) Dual-Core Mobile ZM-82 · 2312552kB/3800016kB
VGA: ATI RS780M/RS780MN [Radeon HD 3200] · ATI Mobility Radeon HD 3400
Loki Harfagr
yes and that's exactly what would fail in case /proc was a link :-)
>
> no need to cd at all ;)
well, read again and use the test and compare lines above ,-)
it's clear that you need either to use the 'cd' *or* to
use 'ls -l /proc/' when you're interested in the content of the
pointer.
Now, note that'd be only if someone made a prank of your /
and made proc a link, and of course the fuzzy nature of /proc
is another story ;-)