Score:1

What is the purpose of cgroup_enable=cpuset cgroup_enable=memory cgroup_memory=1 swapaccount=1

ua flag

I am trying to setup a kubernetes cluster on a raspberry pi cluster using Ubuntu 20.04.3. In many online guides available, one of the steps is mentioned as follows:

Edit the /boot/firmware/cmdline.txt and add cgroup_enable=cpuset cgroup_enable=memory cgroup_memory=1 swapaccount=1 at the end.

The above step is mentioned without any explanation. So, to check my current configuration (without applying the above boot config) I run /proc/cgroups which gives me the following output:

#subsys_name    hierarchy       num_cgroups     enabled
cpuset  8       1       1
cpu     4       43      1
cpuacct 4       43      1
blkio   7       43      1
memory  0       51      0
devices 10      43      1
freezer 3       2       1
net_cls 2       1       1
perf_event      5       1       1
net_prio        2       1       1
pids    6       48      1
rdma    9       1       1

Since swap needs to be disabled, I have checked it is already disabled. As such I have the following questions:

  1. I believe in the output that cpuset is enabled since it has the value of 1 for the enabled column. Am I correct? If so, is explicitly setting cgroup_enable=cpuset necessary?
  2. Since the value under enabled is 0 for memory I believe it is not enabled. Am I correct? If so, what does cgroup_enable=memory and cgroup_memory=1 do? Why do I have to set both of them?
  3. What is the purpose of setting swapaccount=1? Does it make sense to set it if swap is disabled anyway?

cgroups is a new topic to me and as such I would like to know better what each of the commands do instead of blindly copying them.

EDIT: I went through the kernel source code and noticed that nothing called cgroup_memory exists. Yes a function exists by that name but it binds to a command cgroup.memory. So, are all the online blogs talking about cgroup_memory just copied a typo as is?

surya kiran avatar
ae flag
Hi, i'm facing CPUSET missing in CGroup, were you able to solve it .?
mangohost

Post an answer

Most people don’t grasp that asking a lot of questions unlocks learning and improves interpersonal bonding. In Alison’s studies, for example, though people could accurately recall how many questions had been asked in their conversations, they didn’t intuit the link between questions and liking. Across four studies, in which participants were engaged in conversations themselves or read transcripts of others’ conversations, people tended not to realize that question asking would influence—or had influenced—the level of amity between the conversationalists.