Questions tagged [cgroup]
cgroups (control groups) is a Linux kernel feature to limit, account and isolate resource usage (CPU, memory, disk I/O, etc.) of process groups.
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How to find out cgroup of a particular process?
Is there any method to get cgroup of process?
The only one package that I know (cgroup-bin), just provide some manipulations with cgroups and allow to change cgroup of process/list of processes, but ...
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How can I create and use Linux cgroups as a non-root user?
How can I create and use cgroups as a non-root user?
For example, can I, entirely as a non-root user:
create a cgroup with access to one CPU
create a new process in that cgroup
?
I first asked ...
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loop device in a Linux container?
I'm attempting to use a loop device inside a container, to mount some image file:
> sudo losetup /dev/loop0 test.img
losetup: /dev/loop0: failed to set up loop device: No such file or directory
/...
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Systemd fails to run in a docker container when using cgroupv2 (--cgroupns=private)
I will attach the minimized test case below. However, it is a simple Dockerfile that has these lines:
VOLUME ["/sys/fs/cgroup"]
CMD ["/lib/systemd/systemd"]
It is Debian:buster-...
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How does CPU affinity interact with cgroups in Linux?
I'm trying to run multi-threaded benchmarks on a set of isolated CPUs. To cut a long story short, I initially tried with isolcpus and taskset, but hit problems. Now I'm playing with cgroups/csets.
I ...
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Cgroup - no space left on device
I have Debian 7 box and little issue:
mkdir /cgroups/test
echo 500 > /cgroups/test/cpu.shares
echo 3167 > /cgroups/test/tasks
bash: echo: write error: No space left on device
How can I fix it?
...
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Why are applications in a memory-limited LXC container writing large files to disk being killed by the OOM?
EDIT2: This problem appears to exist as well under 3.8.0-25-generic #37-Ubuntu SMP
EDIT: I modified the question from the original title of "Why would the Linux Out of Memory manager be triggered by ...
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How do I set cgroup limits for systemd user slices?
I would like to limit usage of a system on a per user basis. Since Systemd has native support for cgroups, I think using user slices is the way to go.
The problem is: I can't figure out how to set ...
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1
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The memory usage reported in cgroup differs from the free command
Why would the free command be reporting a much different mem usage number vs cgroup?
$ free -b
total used free shared buff/cache available
Mem: 2096914432 ...
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List of controllers empty with cgroup v2
I am trying to learn how cgroups v2 work. I did this:
mount -t cgroup2 none /mnt/cgroup2
That gave me a list of objects in /mnt/cgroup2
root@ubuntu-s-1vcpu-1gb-lon1-01:~# ls -la /mnt/cgroup2/
total ...
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Why are cgroups (blkio serviced bytes) and iotop producing diverging results
I work with lxc user space tools on ubuntu 14.04 and I want to perform some stress tests and benchmarking within a container. I know that free and htop are not working properly in a container.
I am ...
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Why do user and system cpu in cpuacct.stat not add up to cpuacct.usage?
Question relates to Linux cgroups cpu accounting.
I noticed this at the container level, but it persists up to top level. For instance:
# cat /sys/fs/cgroup/cpu/cpuacct.stat /sys/fs/cgroup/cpu/...
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htop cgroup column widen
How can I see full length of text CGROUP column in htop? I cannot enlarge it.
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How to do network accounting using cgroups
I am trying to get network statistics for groups of processes.
As far as I know, complex network accounting on linux is normally done using the accounting infrastructure of netfilter/iptables.
As I'd ...
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Where is my container's memory going?
I have a container leaking memory. Or at least, reported memory consumption goes up fast. If I run top, I get this:
top - 16:56:51 up 6 days, 17:25, 0 users, load average: 0.16, 0.27, 0.31
Tasks: ...
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Applying systemd control group resource limits automatically to specific user applications in a gnome-shell session
Having seen that GNOME now launches apps under systemd scopes I've been looking at a way to get systemd to apply some cgroup resource and memory limits to my browser.
I want to apply a MemoryMax and ...
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How to view cgroups resource control heritage between parents and childs process
Taking for example this hierarchy from systemd-cgls:
└─user.slice
├─user-1000.slice
│ ├─[email protected]
│ │ └─init.scope
│ │ ├─3262 /lib/systemd/systemd --user
│ │ └─3263 (sd-pam)
...
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What is required to activate cgroups in Linux
I have a Debian squeeze kernel (linux-image-2.6.32-5-openvz-amd64) which according to the Doku should support cgroups. When I look into the kernel configuration, it does (or is some other kernel ...
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route traffic from a cgroup via a specific network interface
Is there a possiblity, to restrict a cgroup to a specific network interface? All packets from the cgroup should only be routed via a VPN connection, while other packets use the default route.
With ...
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cgroup fork rejected by pids controller
Have a small server program written in C/C++ that uses nginx and Postgres, currently all are hosted on the same ubuntu system. I usually run the server program from the bash command line.
Recently on ...
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How does systemd put sshd processes in slices?
I'm diagnosing an SSH bastion I manage. This machine has about 5500 SSH connections with port forwarding at any given point in time.
Recently, I ran into an issue where SSH connections where refused ...
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KVM + cgroups: Dom0 process best practice?
I am transitioning from Xen to KVM, and will be using Fedora 14. I plan to use cgroups to assign priorities to VMs.
My question is as follows: If I place VMs in various cgroups, should I also put ...
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What are the advantages/disadvantages of using cgroups?
I administer several Linux-based servers and we are looking at migrating several JBoss apps as well as a couple of websites running on Apache from a RHEL 5.5 (64-bit) server with 4 cores to a RHEL 6 (...
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Use of cores with `isolcpus` and `cpuset`
I have a Red Hat Enterprise Linux Server release 6.9 (Santiago) (I don't manage it). In the GRUB config file I have, let's say, isolcpus=2-32 (out of 36 cores). I also have a cgroup with cpuset=2-32 ...
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Cannot find network subsystem in cgroup on Ubuntu 12.04 LTS
I'm trying to use cgroups to limit a process's network bandwidth, as described in this answer. However, I am unable to find the "files" they refer to. I am using Ubuntu 12.04 LTS with cgroup-bin ...
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Setting the MemoryLimit of a user-created systemd scope using cgroups as user
Related: LImiting overall memory usage for child processes
Is there a way for an unprivileged user, or for root to allow an unprivileged user, to create a systemd scope (or other control group ...
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How to find which cgroup caused OOM?
I'm using cgroup to partition my processes and I'm getting Out Of Memory messages in my kernel logs.
However, I can't find which partition causes them. I've checked the memory controller cgroup but ...
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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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cgroups memory 16GB ceiling
I am trying to use cgroups to limit memory usage of user processes on servers with a large amount of ram (128 GB or more). What we want to achieve is to reserve about 6GB of ram for OS and root ...
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Cannot start cgconfig on Centos 6.5 : cannot mount cpuset to /cgroup/cpuset: Invalid argument
I'd like to try docker-io on Centos 6.5 but the cgconfig daemon will not start:
/etc/init.d/cgconfig restart
Stopping cgconfig service: [ OK ]
Starting cgconfig ...
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cgroup administration and inheritance
In cgroups there seems to be an option called 'cgroup.clone_children' for each subsystem, that allows you to specify if the setting of the parent cgroup should be inherited into the child cgroups. But ...
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0
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`systemctl show` outputs incorrect MemoryCurrent value
on one box, systemctl show get an incorrect value for unit memory usage:
$ systemctl show crond | grep MemoryCurrent
MemoryCurrent=18446744073709551615
18446744073709551615 == UINT64_MAX, this must ...
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0
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cgexec not inheriting LD_LIBRARY_PATH
My /etc/cgconfig.conf file consists of
mount {
cpuset = /cgroup/cpuset;
cpu = /cgroup/cpu;
cpuacct = /cgroup/cpuacct;
memory = /cgroup/memory;
devices = /...
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1
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Linux cgroups cpuset w/ subs causes cgconfig not to start
I am having a problem trying to separate 2 groups using cpuset subsystem. This works fine, however if i go to add a subgroup to that group (in this case -- user1), cgconfig will fail to start with "...
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2
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Kubernetes cgroup driver misconfiguration
Default Docker installation in CentOS starts with systemd Cgroup. I installed Kubernetes from official YUM repo and systemd drop-in 10-kubeadm.conf has the following contents:
[Service]
Environment="...
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Is there a way to set the cgroup that systemd launches a process in?
systemd launches a process in the /system.slice/process-name.service cgroup. I would like to launch the process in a different cgroup. I can do this using cgexec in the ExecStart option, but is there ...
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I can't get the cgroup blkio to throttle the iops of processes in a sub-cgroup
I can't get the cgroup blkio to throttle the iops of processes in a sub-cgroup. I am using CentOS 7, 3.10.0-229. I create the cgroup /sys/fs/cgroup/blkio/user.slice/test1 and do
echo 8:32 10 > /...
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CGroups memory limit not working
I am trying to limit memory usage for a LXC container using CGroups, but I can't limit the memory.
# lxc-cgroup -n maxdaniel981 memory.limit_in_bytes 134217728
lxc_container: failed to assign '...
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systemd: how do I create a new .slice file?
I'm struggling to understand how to set up a new slice on my debian 10 system. I have created a file, system-db.slice by copying system.slice and changing a couple of things:
# This file is part of ...
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Freeze and unfreeze processes transparently?
I'm looking for a way to transparently freeze (pause) a process and then unfreeze it later. This is possible with SIGSTOP, but SIGSTOP causes the parent to be notified (by returning from waitpid), ...
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1
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I/O priority per LVM volume (cgroups)
How can I prioritize LVM volumes I/O performance using cgroups?
I know I can use ionice to make changes at the process level but I wish to be able to do this per LV and not per process.
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Allowed cgroup devices for libvirt/lxc container
I want to allow my libvirt/lxc containers to use tun/tap device. In order to do so I for a running container I can add it to the allowed devices by:
# echo "c 10:200 rwm" > /sys/fs/cgroup/devices/...
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How is the cgroup pam module configured?
Linux has a PAM module that manipulates cgroups. How is it configured (what options does it support?)
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cGroups cgred daemon doesnt always move child processes, parent process temporarily in wrong group
So I'm in the process of setting up CGroups on a few servers, and I'm using the documentation pretty heavily to do this.
I came across this in section 2.8.1 of the Fedora Resource Management Guide (...
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Limit private memory usage per user
I'm using cgroups with the memory controller to set a memory limit for each user (using the memory.limit_in_bytes setting).
The problem is that this setting also accounts cache usage. Therefore, if ...
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How to use cgroup v2 to limit memory and cpu per user group?
With cgroup v1, I can have group configuration in cgconfig.conf and assign groups to different users in cgrules.conf
However, it seems to me that cgconfig and cgrules can't be used along with cgroup ...
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Why LXC requires restart?
LXC documentation says:
Just before you create your first container, you probably should logout and login again,
or even reboot your machine to make sure that your user is placed in the right ...
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Centos 7 & Hard CPU Limits
OS Version Information:
[root@localhost system]# cat /etc/redhat-release
CentOS Linux release 7.1.1503 (Core)
Configuration for the test.slice is as follows:
[root@localhost system]# cat test....
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Restrict I/O Write usage using cgroups
I am trying to restrict I/O write usage on my server using cgroups.
Here is my partition table info:
major minor #blocks name
8 0 10485760 sda
8 1 9437184 sda1
8 ...
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How do I configure LXC to allow the use of SCHED_RR in a container?
Any ideas on how I can configure LXC/cgroups, to allow the use of SCHED_RR for applications in a container?
On the internet I have seen mention of unmounting the cpu-cgroup, I have tried that, ...
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