Linux cgroups (control groups) allow limiting and accounting for resources on a system, including CPU, memory, and block I/O.

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What are the “cpu” and “memory” options on the mount command?

I found some mount commands in a shell script: mount -t cgroup -o memory none /path/XXX mount -t cgroup -o cpu none /path/XXX The question is what does the cpu/memory option mean? I search the ...
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Systemcrash suexec forkbomb.sh ulimits

I got this script named fork.sh: #!/bin/sh forkbomb() { forkbomb | forkbomb & } ; forkbomb If I call it through suexec my whole system will consume 99% cpu. To prevent a normal bash forkbomb I ...
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Does managing cgroups require root access?

I am trying to work with control groups on two different operating systems (Ubuntu and CentoOS). There are few concerns that I would like to ask. I am trying to create a control group using the ...
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Limit system processes using cgroups

My server runs several dozens of processes that are not in my control (mostly monitoring software). According to my application logs, sometimes some of the third party processes try to allocate too ...
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23 views

My systemd slices aren't reporting info to systemd-cgtop

I have a centos VM running via KVM on my Debian laptop. This is what I see when I run systemd-cgtop: I know I have a user,system,and machine slice, but I'm only seeing data from the machine slice. ...
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mkdir under /cgroup creates files along with directories

All this while I have been thinking that mkdir can only create directories. But I am surprised to see that it was able to create files also under some conditions. I recently started working with ...
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vagrant user able to switch to any user without any password while running command “sudo su - <username>” but other users doesn't

I have installed two vagrant hosts on my machine. I login using user/pass: vagrant/vagrant Created a user user1. When I am in vagrant user and type below command : [vagrant@host1]sudo su - I am ...
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47 views

cgconfig.conf file is missing

I installed cgroup on my linux (3.19.0+) using the following command: apt-get install cgroup-bin However I can't find the file /etc/cgconfig.conf. Did I miss anything?
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183 views

How to calculate blkio shares in cgroups?

Currently I'm trying to setup a test scenario with the use of Debian Wheezy with its default kernel 3.2.60-1+deb7u3 and the cgroups blkio controller. The calculation of blkio.weight is not working for ...
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798 views

cgroups, cpuset changing the cpuset of some processes fail

I am trying to "reserve" a core on a CPU for performance measurement. I have mounted a cpuset cgroups vfs. I created two subgroups like this: /cpuset.cpu_exclusive 1 /cpuset.cpus 0-3 ...
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Cgroups Memory Related Questions

1) Why cgroup is showing more number of tasks than actual number of tasks.? Ex : [root@localhost proc]# ps -aux | wc -l 421 [root@localhost proc]# cat /sys/fs/cgroup/memory/tasks | wc -l 539 2) ...
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Cannot set memory.memsw.limit_in_bytes in cgroup on Ubuntu server using cgm

I'm trying to limit resource usage for a cgroup without having root access. I can set memory.limit_in_bytes using cgm setvalue memory memory.limit_in_bytes 150G But I can not set ...
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How to create user cgroups with systemd

I use unprivileged lxc containers in Arch Linux. Here are the basic system infos: [chb@conventiont ~]$ uname -a Linux conventiont 3.17.4-Chb #1 SMP PREEMPT Fri Nov 28 12:39:54 UTC 2014 x86_64 ...
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Get quota usage information as non-privileged user

I have non-privileged access to a Linux server (shared PHP+MySQL hosting) and there are disk space, memory, CPU usage, I/O quotas. I wonder how can I get information about max/current quota usage ...
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Does high Load average cgroups give “wrong” overall load average

Assume you have a system with 2 processors. Now create a cgroup and configure this group to use only 1 processor. Populate it with enough processes to give it a load average of 5 (to prove a point); ...
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Centos 6 to Centos 7 cgroups

I'm trying to set up resource limits per user in Centos 7, but I can't find the right commands for the new implementation of cgroups (I did read the documentation but it talks about restricting ...
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How to use cgroups to limit all processes except whitelist to a single CPU?

There is a guide to cgroups from Red Hat which is maybe sort of kind of helpful (but doesn't answer this question). I know how to limit a specific process to a specific CPU, during the command to ...
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190 views

Why cgroup cpu items are miss in Debian 8

the kernel version for debian 8 use 3.10. But under /sys/fs/cgroup/cpu, miss a lot of cpu items. vagrant@debian-jessie:/sys/fs/cgroup/cpu$ ls -1 . cgroup.clone_children cgroup.procs ...
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145 views

Using tc for traffic quotas?

Is it possible to implement traffic quotas (absolute limits, not rate limits) based on the network classifier cgroup? I see there is the iptables netfilter 'quota' extension, which seems to do ...
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reserve resources for admin console

My server is often almost DOS'ed by crawlers. I have not yet managed to figure out what exactly is responsible for the high load. CPU, memory and disk IO are not at the limit (could be network ...
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1answer
133 views

How to limit Skype CPU usage

I use Skype only for messaging. But it is consuming some CPU time when idle. So, I need to limit only one process and only for the CPU usage. Can that be done easily? I am a complete newbie to Linux ...
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cgroups: cgclassify processes of other users

As root I've create a cgroup which limits cpu and memory usage. cgcreate -g cpu,memory:matlab_sandbox cgset -r cpu.shares=250 matlab_sandbox cgset -r memory.limit_in_bytes=8G matlab_sandbox Now I'm ...
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Externaly limiting number of CPU cores used

I need to externally limit a process/session to a certain number of cores. Are there any other possibilities than CPU affinity (I don't like the need to specify the actual cores) and cgroups (hard to ...
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268 views

Permanent swapping with lots of free memory

We have a Linux server running Debian 4.0.5 (Kernel 4.0.0-2) with 32G RAM installed and 16G Swap configured. The system uses lxc containers for compartmentalisation, but that shouldn't matter here. ...
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What is “state-object” in cgroups

I am gathering some idea about lxc, kernel name spaces and cgroups. While reading man lxc-cgroup, i find : lxc-cgroup gets or sets the value of a state-object (e.g., 'cpuset.cpus') in the ...
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How do cgroups interact with non-cgrouped processes?

I have 3 processes on a single core machine. Each process is exactly the same and burns CPU as fast as it can (tight loop). Two of them (A and B) are launched with cgexec in separate groups with ...
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472 views

Linux cgroups: limit CPU usage in absolute values which do not depend on CPU speed

I have a server with a 2.4GHz processor. And there are several cgroups, each one allowed to use 25% of CPU. That's equal to 600MHz. Then I replace the CPU with a faster one, let's say 3.0GHz. If I ...
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How to set a process’s sched method to fifo and priority when cgroup are on?

I’m using CentOS 6.6, I want to set the sched method of my kvm VM to FIFO with priority 1. First, I use chrt and get error: chrt(): "failed to set pid XXX's policy" I find here: chrt(): ...
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20 views

Configure scheduling to a program

The program "checking" should be autostart when the machine boot and should be start always with scheduling round robin with priority 27 in Rhel/Centos 7. I can configure this scheduling with cgroups ...
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Sandboxing a binary on linux

I am trying to understand various options I have to restrict/sandbox a binary in Linux. I see that I can use namespaces and cgroups like docker does. I could use SELinux like this link suggests. Which ...
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How to mount cgroups controllers using cgconfig.conf, while systemd running

I am trying to create a basic cgroups setup on a few Fedora 20 servers (using cgconfig and cgred services). The problem is I would like to create a hierarchy with access to several ...
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How do I read from memory.pressure_level in a cgroup?

I want to see the memory pressure of the cgroup. But simple cat memory.presure_level fails. How do I know the current memory pressure of a cgroup?
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287 views

ubuntu lts and cgroup support in iptables [closed]

I don't understand why Ubuntu community built iptables without cgroup support and what I don't understand if community didn't make it? Maybe Ubuntu use another some way (iptables without cgroup etc)? ...
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261 views

how to set cpuset/cgroup.clone_children flag to 1

I am trying to set the cpuset/cgroup.clone_children to 1 so that whenever I create a cgroup, it should by default copy all values from the parent cgroup. Also I am curious if there is a way to copy ...
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31 views

Adding entire session to a cgroup

How would I add entire session to a cgroup. cgclassify seems to add just the specified PID.
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cgroup memory.usage_in_bytes always zero for some tasks

I am trying to use cgroup to manage memory on a HPC cluster using torque queue manager on CentOS 6 machines. Just to test I login to a node running a job where I have: ...
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Creating one-time cgroup

I would like to be able to create a one-time temporary group in hierarchy. For example: #!/bin/sh run_with_csubgroup /sys/fs/cgroup/group/subgroup/ Which creates group say ...
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High on %wa from top command, is there any way to constrain it?

Here's my last top info before it stucks: top - 18:26:10 up 238 days, 5:43, 3 users, load average: 1782.01, 1824.47, 1680.36 Tasks: 1938 total, 1 running, 1937 sleeping, 0 stopped, 0 zombie ...
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How to ensure ssh via cgroups on centos?

When some cpu-intensive processes are running on the server, chances are that we could not log in to this machine with error 'operation timeout' via ssh command. According to this post answered by ...
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Using Cgroups with Systemd to restrict bash cpu & memory

I want to restrict every user on my Centos 7 server who is logged in via SSH. They should not be able to use, for example, a forkbomb and kill the whole system. The superuser will have no restriction. ...
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Why my limit on CPU does not validate via cgroups

/etc/cgconfig.conf ... group memlimit { memory { memory.limit_in_bytes = 8589934592; } } group cpulimit { cpu { cpu.shares = 1024; } } /etc/cgrules.conf: ...
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How to enable swap accounting for memory cgroup in Archlinux?

On my Archlinux box I want to limit some applications to a smaller amount of memory using cgroups. Since I use swap, I need to account memory+swap. How can I enable swap accounting?
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A way to set parameters in the LXC parent cgroups

So I have LXC installed, guest containers configured and all. The LXC containers each go into their own submodule (in cgroup parlance) and each are configured with cpu.shares and also the memory ...
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LINUX processes are forking up to thousand of processes again, even after kill command

On one of our boxes, I'm encountering strange problem from time to time.. in.tftpd processes are forking up to thousand of processes, getting server to almost unresponsive state. I've tried various ...
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143 views

Distributing CPU cores between cgroups and outside world

Is it possible to manage access to CPU cores in a similar fashion that memory limiting works? In particular I need to be able to dynamically create and destroy cgroups that will limit a particular ...
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Simplest possible secure sandboxing (limited resources needed)

I'm working on a project that implements distributed simulations: arbitrary code is executed on multiple nodes and the results are later collected and aggregated. Each node is an instance of an ...
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How to jail a fastcgi server (or a web-proxied server)?

If you have a web-server (e.g. nginx) often you use a fast-cgi server or another application-http-server for dynamic content. That means in both cases you have a nice process separation between the ...
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Need help finding the CPU id numbers to use with cpu sets

The man for cpuset doesn't seem to clearly list how to figure out which numbers map to which processing units. My current machine has two Intel Xeon E5645s, each of which has 6 cores and ...
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receive signal before process is being killed by OOM killer / cgroups

In our cluster, we are restricting our processes resources, e.g. memory (memory.limit_in_bytes). I think, in the end, this is also handled via the OOM killer in the Linux kernel (looks like it by ...
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cgroups: blkio.weight doesn't seem to have the expected effect

I've got 2 LXC containers with these cgroup settings: lxc.cgroup.blkio.weight = 200 lxc.cgroup.cpu.shares = 200 and lxc.cgroup.blkio.weight = 800 lxc.cgroup.cpu.shares = 800 I have verified in ...