Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [limit]

Limiting the usage of a resource (memory, disk space, CPU time, open files, network bandwidth, …) by a process or a group of processes.

A limit is a restriction on a program that prevents it from using more than a set amount of resources, such as memory, disk space, CPU time, open files, network bandwidth, etc.

The ulimit built-in of POSIX shells lets a user set limits on the shell process and the programs that it subsequently invokes. The set of supported resources varies depending on the shell and the operating system.

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do changes in /etc/security/limits.conf require a reboot?

Do changes in /etc/security/limits.conf require a reboot before taking effect? For example, if I have a script that sets the following limits in /etc/security/limits.conf, does this require a system reboot before those limits will take effect? *…
Alexej Magura
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How do I limit the number of files printed by ls?

Is there a way to limit the quantity of listed files on a ls command? I've seen: ls | head -4 but to get head or tail to be executed I need to wait for ls to finish execution, and with directories with an enourmous quantity of files that can take…
AndreDurao
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Why is number of open files limited in Linux?

Right now, I know how to: find open files limit per process: ulimit -n count all opened files by all processes: lsof | wc -l get maximum allowed number of open files: cat /proc/sys/fs/file-max My question is: Why is there a limit of open files in…
xanpeng
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How to limit a process to one CPU core in Linux?

How to limit process to one cpu core ? Something similar to ulimit or cpulimit would be nice. (Just to ensure: I do NOT want to limit percentage usage or time of execution. I want to force app (with all it's children, processes (threads)) to use one…
Grzegorz Wierzowiecki
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Creating threads fails with “Resource temporarily unavailable” with 4.3 kernel

I am running a docker server on Arch Linux (kernel 4.3.3-2) with several containers. Since my last reboot, both the docker server and random programs within the containers crash with a message about not being able to create a thread, or (less often)…
cdauth
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How to create a user with limited RAM usage?

So I have 4 GB RAM + 4GB swap. I want to create a user with limited ram and swap: 3 GB RAM and 1 GB swap. Is such thing possible? Is it possible to start applications with limited RAM and swap avaliable to them without creating a separate user (and…
myWallJSON
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How can I increase open files limit for all processes?

I can use ulimit but I think that only affects my shell session. I want the limit increased for all processes. This is on Red Hat.
user5554
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Limiting processes to not exceed more than 10% of CPU usage

I operate a Linux system which has a lot of users but sometimes an abuse occurs; where a user might run a single process that uses up more than 80% of the CPU/Memory. So is there a way to prevent this from happening by limiting the amount of CPU…
Giovanni Mounir
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Modify ulimit (open files) of a specific process

Is it possible to change the soft - and hard limit of a specific process? In my case, my process is mongod and a lot of web resources tell me to simply execute: ulimit -n My current thoughts: How will the command know the limit of…
test
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Is there a way to limit the amount of memory a particular process can use in Unix?

I need to test a process for memory management. I do not have the source, so I need to do all the testing from the OS side. I want to be able to say something like limitmemory 400k -p Is there a way to do this in unix? Any common unix…
Lazer
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How to Throttle per process I/O to a max limit?

I'm looking for a way to limit a processes disk io to a set speed limit. Ideally the program would work similar to this: $ limitio --pid 32423 --write-limit 1M Limiting process 32423 to 1 megabyte per second hard drive writing speed.
Sepero
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Limit max connections per IP address and new connections per second with iptables

We have an Ubuntu 12.04 server with httpd on port 80 and we want to limit: the maximum connections per IP address to httpd to 10 the maximum new connections per second to httpd to 150 How can we do this with iptables?
evachristine
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sudo: ulimit: command not found

On Ubuntu 12.04, I ran ulimit -n, it is showing 1024. I want to increase my open file limit from 1024 to 65535, so I tried the following command: sudo ulimit -n 65535 but I get the following error: sudo: ulimit: command not found How do I…
sunpy
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Make disk/disk copy slower

Is there a method of slowing down the copy process on Linux? I have a big file, say 10GB, and I'd like to copy it to another directory, but I don't want to copy it with full speed. Let's say I'd like to copy it with the speed of 1mb/s, not faster.…
antonone
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How to limit log file size using >>

How can I limit the size of a log file written with >> to 200MB? $ run_program >> myprogram.log
david
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