Beefy Boxes and Bandwidth Generously Provided by pair Networks
Your skill will accomplish
what the force of many cannot
 
PerlMonks  

Scheduling script with pauses

by goshawk (Initiate)
on Oct 10, 2013 at 01:40 UTC ( #1057651=perlquestion: print w/ replies, xml ) Need Help??
goshawk has asked for the wisdom of the Perl Monks concerning the following question:

I want to run a script that takes at least a week to run, on a computer that is used for other purposes during the day. Is it possible to pause the script at a given hour, say 6 AM, temporarily write everything in memory to a file until another given hour, say 9 PM, and then resume?

I would try to write the script so that it could be broken into parts, but it's a single line leading to a black-box C interface that takes so many days. It's okay if this isn't possible; it would just be easier if it would be.

Not sure if it matters, but this is on a Unix system.

Comment on Scheduling script with pauses
Re: Scheduling script with pauses ( suspend-to-disk )
by Anonymous Monk on Oct 10, 2013 at 01:55 UTC

    but it's a single line leading to a black-box C interface that takes so many days

    And there in lies the problem -- without cooperation its not going to work well

    Most computers have a "hibernate" mode, aka syspend-to-disk, and it works when every program is suspended including the operating system, and the memory is dumped to a pagefile on the disk

    hibernating a single process can get very tricky ... but I imagine if you've got the RAM, and you run a virtual machine, you can simply hibernate the virtual machine ...

    Good luck

Re: Scheduling script with pauses
by BrowserUk (Pope) on Oct 10, 2013 at 02:52 UTC

    Under Windows, I often use the ProcessManager to pause a process; and then later resume it. Provided the machine isn't shutdown or re-started, this works well. Even if it is using a substantial amount of memory, once paused, any other processes that need memory simple cause its memory to get swapped out; and it get swapped back in once resumed.

    Try: kill -STOP <yourpid> and then later: kill -CONT <yourpid>.


    With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
    "Science is about questioning the status quo. Questioning authority".
    In the absence of evidence, opinion is indistinguishable from prejudice.
Re: Scheduling script with pauses
by dmitri (Curate) on Oct 10, 2013 at 03:49 UTC
    It's quite easy, just send suspend and resume signals to the process:
    sh$ kill -STOP $pid # this suspends it sh$ kill -CONT $pid # this resumes it
    You can stick that in your crontab. If there is a process group to suspend and resume, use -$pid. Pretty much, read kill(2) man page.

    Update: I see this answer was given already, I did not read to the end of BrowserUk's post first time around (I gave up around "Windows" :))

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: perlquestion [id://1057651]
Approved by Athanasius
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others avoiding work at the Monastery: (3)
As of 2014-10-02 00:21 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    What is your favourite meta-syntactic variable name?














    Results (41 votes), past polls