Re: Enhancement/feature idea for GNU parallel

[Ole Tange]

On Sat, Feb 19, 2011 at 5:16 PM, David Bennion <david.bennion@gmx.com> wrote:
>
> Hey Ole,
>
> I wanted to solve a problem (parallel encoding mp3s and also parallel runs of 
> ffmpeg).  I didn’t know parallel existed and I had not used xargs before, but 
> I have been able to really use parallel and gain performance from my 4-way 
> system.  So thanks for your efforts.

Glad you like it.

> The idea that I had that I thought would be neat is if you could pass in N 
> number of device consoles (/dev/pts/1 /dev/pts/2 /dev/pts/3) and if parallel 
> would reopen stdout, stderr and stdin for child processes.  The net effect 
> would be that you could create multiple login shells/windows on your box and 
> you could watch in real time as each job runs – whichever console it ends up 
> on.
>
> This is not really something that could be done by the jobs themselves 
> because the consoles need to be selected based on which processor the jobs 
> get run on.  It would be an error if not enough console devices were passed 
> in, they need to match 1 to 1 with processors/job threads.

As I understand you would need to:

1: Open terminals for each process you want run in parallel
2: Run "tty" in each of them to get the devicename
3: Pass these outputs to GNU Parallel on the command line
4: Run the parallel command

It seems like an awful lot of work just to be able to monitor
progress. Especially with encoding which you would often just run as a
script.

It is quite some work to implement this feature and I am afraid that
extremely few users will be using it. So unless you convince other
users that your idea is needed I so not see it being implemented.

With --logfile, --progress or -u you can already watch the progress.


/Ole