Difference between revisions of "Ulimit"

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[[Category:Basics]]
 
== General ==
 
== General ==
 
ulimit is a tool to print and control user limits on a Linux system
 
ulimit is a tool to print and control user limits on a Linux system
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The ulimit command line tool allows to print the user limits for certain recources within the current shell:
 
The ulimit command line tool allows to print the user limits for certain recources within the current shell:
  
$ ulimit -a
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$ ulimit -a
  
 
Furthermore, the ulimit command can be used to set a limit to a differnt value.
 
Furthermore, the ulimit command can be used to set a limit to a differnt value.
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1. When a program uses more memory for the stack than allowed, this leads to a SEGFAULT during execution of the program. This happens quite often for Fortran programs. In such cases increasing the stacksize with one of the following commands can help:
 
1. When a program uses more memory for the stack than allowed, this leads to a SEGFAULT during execution of the program. This happens quite often for Fortran programs. In such cases increasing the stacksize with one of the following commands can help:
  
$ ulimit -s 100000
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$ ulimit -s 100000
or
+
or
$ ulimit -s unlimited
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$ ulimit -s unlimited
  
 
2. On frontend nodes often a timelimit is set for processes to avoid that people start long running applications and distub other users. For IDEs or debuggers this can be a bad idea, since the limit might kill the debugger or the IDE after some time without any warning or message. In such cases deactivating the timelimit before starting the IDE is useful:
 
2. On frontend nodes often a timelimit is set for processes to avoid that people start long running applications and distub other users. For IDEs or debuggers this can be a bad idea, since the limit might kill the debugger or the IDE after some time without any warning or message. In such cases deactivating the timelimit before starting the IDE is useful:
  
$ ulimit -t unlimited
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$ ulimit -t unlimited
  
  
 
== FAQs ==
 
== FAQs ==
 
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[https://ss64.com/bash/ulimit.html ulimit manpage]
  
 
== Side specific information ==
 
== Side specific information ==

Latest revision as of 09:23, 5 September 2019

General

ulimit is a tool to print and control user limits on a Linux system

Manual

The ulimit command line tool allows to print the user limits for certain recources within the current shell:

$ ulimit -a

Furthermore, the ulimit command can be used to set a limit to a differnt value. The most frequent cases when this is needed is: 1. When a program uses more memory for the stack than allowed, this leads to a SEGFAULT during execution of the program. This happens quite often for Fortran programs. In such cases increasing the stacksize with one of the following commands can help:

$ ulimit -s 100000
or
$ ulimit -s unlimited

2. On frontend nodes often a timelimit is set for processes to avoid that people start long running applications and distub other users. For IDEs or debuggers this can be a bad idea, since the limit might kill the debugger or the IDE after some time without any warning or message. In such cases deactivating the timelimit before starting the IDE is useful:

$ ulimit -t unlimited


FAQs

ulimit manpage

Side specific information