linux:kernel:control_groups
Differences
This shows you the differences between two versions of the page.
| Both sides previous revisionPrevious revisionNext revision | Previous revision | ||
| linux:kernel:control_groups [2019/12/15 21:49] – peter | linux:kernel:control_groups [2020/07/15 09:30] (current) – external edit 127.0.0.1 | ||
|---|---|---|---|
| Line 15: | Line 15: | ||
| User level code may create and destroy cgroups by name in an instance of the cgroup virtual file system, specify and query to which cgroup a task is assigned, and list the task pids assigned to a cgroup. Those creations and assignments only affect the hierarchy associated with that instance of the cgroup file system. | User level code may create and destroy cgroups by name in an instance of the cgroup virtual file system, specify and query to which cgroup a task is assigned, and list the task pids assigned to a cgroup. Those creations and assignments only affect the hierarchy associated with that instance of the cgroup file system. | ||
| - | On their own, the only use for cgroups is for simple job tracking. The intention is that other subsystems hook into the generic cgroup support to provide new attributes for cgroups, such as accounting/ | + | On their own, the only use for cgroups is for simple job tracking. The intention is that other subsystems hook into the generic cgroup support to provide new attributes for cgroups, such as accounting/ |
| ---- | ---- | ||
| Line 21: | Line 21: | ||
| ===== Why are cgroups needed? ===== | ===== Why are cgroups needed? ===== | ||
| - | There are multiple efforts to provide process aggregations in the Linux kernel, mainly for resource tracking purposes. Such efforts include [[Kernel: | + | There are multiple efforts to provide process aggregations in the Linux kernel, mainly for resource tracking purposes. Such efforts include [[Linux:Kernel:CPU Sets|cpusets]], |
| - | The kernel cgroup patch provides the minimum essential kernel mechanisms required to efficiently implement such groups. | + | The kernel cgroup patch provides the minimum essential kernel mechanisms required to efficiently implement such groups. |
| Multiple hierarchy support is provided to allow for situations where the division of tasks into cgroups is distinctly different for different subsystems - having parallel hierarchies allows each hierarchy to be a natural division of tasks, without having to handle complex combinations of tasks that would be present if several unrelated subsystems needed to be forced into the same tree of cgroups. | Multiple hierarchy support is provided to allow for situations where the division of tasks into cgroups is distinctly different for different subsystems - having parallel hierarchies allows each hierarchy to be a natural division of tasks, without having to handle complex combinations of tasks that would be present if several unrelated subsystems needed to be forced into the same tree of cgroups. | ||
| Line 115: | Line 115: | ||
| * **release_agent**: | * **release_agent**: | ||
| - | Other subsystems such as [[Kernel: | + | Other subsystems such as [[Linux:Kernel:CPU Sets|cpusets]] may add additional files in each cgroup dir. |
| New cgroups are created using the mkdir system call or shell command. | New cgroups are created using the mkdir system call or shell command. | ||
| Line 453: | Line 453: | ||
| </ | </ | ||
| - | Called at the end of **cgroup_clone()** to do any parameter initialization which might be required before a task could attach. | + | Called at the end of **cgroup_clone()** to do any parameter initialization which might be required before a task could attach. |
| <code c> | <code c> | ||
linux/kernel/control_groups.1576446558.txt.gz · Last modified: 2020/07/15 09:30 (external edit)