linuxgeek: Re: [LINUX_Newbies] Re: How to control traffic in Linux?

Tuesday, January 7, 2014

Re: [LINUX_Newbies] Re: How to control traffic in Linux?

Good morning
Di Jan 07 10:06:37 2014
Thank You for email and help.

Am 03.01.2014 00:17, schrieb Cameron Simpson:> On 02Jan2014 16:56,
highskywhy@yahoo.de <highskywhy@yahoo.de> wrote:
> > > > zip is very unimportant and should work very slow
> > > > how can I start zip and zip should use only a small part of
the cpu
> > >
> > > nohup nice -n 15 zip command that is long >/dev/null >>/dev/null &
> > *
> > Sorry
> > I do not understand.
>
> What, specificly?
*
nohup

>
> There are three commands above:
>
> nohup ...
*
Thank You
this was the problem.
>
> which dispatches the command "..." ignoring SIGHUP (which happens
> at log out, window close, etc), with its output directed to the
> file "nohup.out".
*
OK

>
> Then the command "..." is "nice -n 15 zip command that is long".
>
> That one is itself two commands:
>
> nice -n 15 ...
>
> which runs the command "..." with greater niceness.
*
OK

>
> Then the command "..." is "zip command that is long" which I'm
> taking to mean your chosen zip command. I suspect Trevor's example
> originally was "command that is long" and then he inserted "zip".
*
OK
>
> The redirections ">/dev/null >>/dev/null" are not really necessary
> or useful with nohup, and incorrrectly phrased anyway.
*
OK
>
> The final "&" is to put the command into the background i.e. you
> get your prompt back immediately. If you nohup a command it is
> generally because you do not want to wait for it to finish.
*
OK
>
> > > the 15 can be any number from 11 (slightly less important) to 20
(Only
> > > when there is nothing else to do) 20 will run very slowly!
> > *
> > 11 is slow.
> > What number is fast?
>
> As Trevor's pointed out, negative numbers are "faster" - less nice.
*
THANK YOU
>
> However, you can also take the approach that your shell is "full
> speed" and that you only ever need to slow things down, so you only
> need to make things nicer, not less nice.
*
OK
>
> And it bears repeating: if you are only running one command that
> is CPU intensive then the niceness is irrelevant, because it only
> affects the share of the CPU given to the command.
>*
Ok

> "nice" is not slow: it is slower than other things.
>

Thank You

Regards
Sophie