Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [scheduling]

A technique for scheduling tasks to be run at a specific time or on a specific event.

The use of this tag should pertain to the UNIX facilities CRON, at, or that are backgrounded using a shell's jobs capability. Additionally there are sub-components to the kernel that also utilize scheduling, and so using this tag for these would also be appropriate.

410 questions
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How can get a list of all scheduled cron jobs on my machine?

My sysadmin has set up a bunch of cron jobs on my machine. I'd like to know exactly what is scheduled for what time. How can I get that list?
Frank
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Where are cron errors logged?

If I setup cron jobs incorrectly they appear to silently fail. Where should I look for an error log to understand what went wrong?
Brian Lyttle
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How to shutdown Linux at specific datetime from terminal?

It seems I can shutdown using sudo shutdown by specifying a time or minutes. Is there a way to specify datetime for shutdown?
Askar
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Run script every 30 min with systemd

I would like to execute a script every 30 min after booting into the system. I know you can use cron, but I don't plan to use this feature often therefore I'd like to try it with systemd. So far I have only found the monotonic timers which allows to…
TomTom
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Real time processes scheduling in Linux

I have been learning some scheduling concepts. Currently my understanding so far is as below. There are real time processes and non real time processes. Non real time processes can have nice values for their priority in the range of -20 to +20.…
Ramesh
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Start/stop a systemd.service at specific times

I want to start and stop a systemd.service at specific times. Presumably I will use a .timer unit to start the job, but is there a built in way to stop the job after a specific duration, or at a specific time, or do I have to create a second .timer…
Jamie Kitson
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Is there a way to auto turn-on Linux machine?

I know that there are many ways to auto-shutdown, but I'm concerned about auto turn-on. Is there a command or a small piece of software to turn on the system at given time?
remas sido
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High CPU usage with CFS?

I asked a previous question to try and isolate the source of an increase in CPU usage when moving an application from RHEL 5 to RHEL 6. The analysis that I did for that seems to indicate that it is being caused by the CFS in the kernel. I wrote a…
Dave Johansen
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Why does niceness range from -20 to 19?

The nice command allows you to adjust the scheduling priority ("niceness") of a program. On all Unix-like systems I've used, niceness is specified by a range of integers, where -20 is the most favourable scheduling priority, 0 is the default, and…
Psychonaut
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How is nice working?

sched_setscheduler says : All scheduling is preemptive: if a process with a higher static priority becomes ready to run, the currently running process will be preempted and returned to the wait list for its static priority …
BЈовић
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Does `at` run a command later if the computer is off at the specified time?

I want to schedule jobs with at, but I'm not sure what happens if the computer is suspended at the specified time: Will the command be executed as soon as the computer wakes up again (like with anacron) or will it not be executed at all (like with…
dessert
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Using and understanding systemd scheduling-related options in a desktop context

In systemd service files, one can set the following scheduling related options (from the systemd.exec man page, correct me if I'm wrong): Nice Sets the default nice level (scheduling priority) for executed processes. Takes an integer…
equaeghe
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How do I view the IO priority of a process?

How can I view the IO priority of a process? like to see for example if something has been ionice-ed.
xenoterracide
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How to enable and use the BFQ scheduler?

I just installed Linux kernel version 4.12 on Ubuntu 17.04 using ukuu (Ubuntu Kernel Update Utility https://doc.ubuntu-fr.org/ubuntu_kernel_upgrade_utility). The thing is, when I check the available I/O schedulers, I can't seem to find the BFQ nor…
Sidahmed
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What does "INFO: task XXX blocked for more than 120 seconds" exactly mean on Linux?

I had this message in my kernel log : INFO: task XXX blocked for more than 120 seconds. I would like to know what it means technically: under what conditions does the kernel display this message about a task? For the record, my blocked task was…
Totor
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