CGroupsManager (Apache UIMA DUCC: uima-ducc-agent 2.0.0 API)

java.lang.Object
- org.apache.uima.ducc.agent.launcher.CGroupsManager

```
public class CGroupsManager
extends Object
```
Manages cgroup container on a node Supported operations: - cgcreate - creates cgroup container - cgset - sets max memory limit for an existing container

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

class CGroupsManager.NodeProcessInfo

Nested Classes
Modifier and Type	Class and Description
`class`	`CGroupsManager.NodeProcessInfo`

Constructor Summary

Constructors
Constructor and Description
`CGroupsManager(String cgroupUtilsDir, String cgroupBaseDir, String cgroupSubsystems, org.apache.uima.ducc.common.utils.DuccLogger agentLogger)`

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`cgroupExists(String cgroup)`
`void`	`cleanupOnStartup()` Finds all stale CGroups in /cgroup/ducc folder and cleans them up.
`Set<String>`	`collectExistingContainers()` Return a Set of existing cgroup Ids found in the filesystem identified by 'cgroupBaseDir'.
`boolean`	`createContainer(String containerId, String userId, boolean useDuccSpawn)` Creates cgroup container with a given id and owner.
`boolean`	`destroyContainer(String containerId)` Removes cgroup container with a given id.
`String[]`	`getAllCGroupPids()` Returns an array of PIDs managed by cgroups.
`String`	`getCGroupsUtilsDir()`
`String`	`getContainerId(ManagedProcess managedProcess)`
`String`	`getDuccCGroupBaseDir()`
`String[]`	`getPidsInCgroup(String cgroupName)`
`Set<CGroupsManager.NodeProcessInfo>`	`getProcessesOnNode()`
`String`	`getSubsystems()`
`boolean`	`isPidInCGroup(String pid)`
`void`	`kill(String user, String pid)`
`static void`	`main(String[] args)`
`boolean`	`setContainerCpuShares(String containerId, String userId, boolean useDuccSpawn, long containerCpuShares)` Sets the cpu shares use for an existing cgroup container.
`boolean`	`setContainerMaxMemoryLimit(String containerId, String userId, boolean useDuccSpawn, long containerMaxSize)` Sets the max memory use for an existing cgroup container.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - CGroupsManager
```
public CGroupsManager(String cgroupUtilsDir,
              String cgroupBaseDir,
              String cgroupSubsystems,
              org.apache.uima.ducc.common.utils.DuccLogger agentLogger)
```
- Method Detail
  - main
```
public static void main(String[] args)
```
    Parameters:
    args -
  - getCGroupsUtilsDir
```
public String getCGroupsUtilsDir()
```
  - getPidsInCgroup
```
public String[] getPidsInCgroup(String cgroupName)
                         throws Exception
```
    Throws:
    
    Exception
  - cleanupOnStartup
```
public void cleanupOnStartup()
                      throws Exception
```
    Finds all stale CGroups in /cgroup/ducc folder and cleans them up. The code only cleans up cgroups folders with names that follow ducc's cgroup naming convention: ... First, each cgroup is checked for still running processes in the cgroup by looking at /cgroup/ducc//cgroup.proc file which includes PIDs of processes associated with the cgroups. If processes are found, each one is killed via -9 and the cgroup is removed.
    
    Throws:
    
    Exception
  - isPidInCGroup
```
public boolean isPidInCGroup(String pid)
                      throws Exception
```
    Throws:
    
    Exception
  - getAllCGroupPids
```
public String[] getAllCGroupPids()
                          throws Exception
```
    Returns an array of PIDs managed by cgroups.
    
    Returns:
    - String array of PIDs
    
    Throws:
    
    Exception
  - kill
```
public void kill(String user,
        String pid)
```
  - getContainerId
```
public String getContainerId(ManagedProcess managedProcess)
```
  - createContainer
```
public boolean createContainer(String containerId,
                      String userId,
                      boolean useDuccSpawn)
                        throws Exception
```
    Creates cgroup container with a given id and owner.
    
    Parameters:
    containerId - - new cgroup container id
    userId - - owner of the cgroup container
    useDuccSpawn - - use duccling to run 'cgcreate' command
    
    Returns:
    - true on success, false otherwise
    
    Throws:
    
    Exception
  - setContainerMaxMemoryLimit
```
public boolean setContainerMaxMemoryLimit(String containerId,
                                 String userId,
                                 boolean useDuccSpawn,
                                 long containerMaxSize)
                                   throws Exception
```
    Sets the max memory use for an existing cgroup container.
    
    Parameters:
    containerId - - existing container id for which limit will be set
    userId - - container owner
    useDuccSpawn - - run 'cgset' command as a user
    containerMaxSize - - max memory limit
    
    Returns:
    - true on success, false otherwise
    
    Throws:
    
    Exception
  - setContainerCpuShares
```
public boolean setContainerCpuShares(String containerId,
                            String userId,
                            boolean useDuccSpawn,
                            long containerCpuShares)
                              throws Exception
```
    Sets the cpu shares use for an existing cgroup container.
    
    Parameters:
    containerId - - existing container id for which limit will be set
    userId - - container owner
    useDuccSpawn - - run 'cgset' command as a user
    containerCpuShares - - cpu shares
    
    Returns:
    - true on success, false otherwise
    
    Throws:
    
    Exception
  - destroyContainer
```
public boolean destroyContainer(String containerId)
                         throws Exception
```
    Removes cgroup container with a given id. Cgroups are implemented as a virtual file system. All is needed here is just rmdir.
    
    Parameters:
    containerId - - cgroup to remove
    
    Returns:
    - true on success, false otherwise
    
    Throws:
    
    Exception
  - collectExistingContainers
```
public Set<String> collectExistingContainers()
                                      throws Exception
```
    Return a Set of existing cgroup Ids found in the filesystem identified by 'cgroupBaseDir'.
    
    Returns:
    - set of cgroup ids
    
    Throws:
    
    Exception
  - getDuccCGroupBaseDir
```
public String getDuccCGroupBaseDir()
```
  - getSubsystems
```
public String getSubsystems()
```
  - cgroupExists
```
public boolean cgroupExists(String cgroup)
                     throws Exception
```
    Throws:
    
    Exception
  - getProcessesOnNode
```
public Set<CGroupsManager.NodeProcessInfo> getProcessesOnNode()
                                                       throws Exception
```
    Throws:
    
    Exception

Class CGroupsManager

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

CGroupsManager

Method Detail

main

getCGroupsUtilsDir

getPidsInCgroup

cleanupOnStartup

isPidInCGroup

getAllCGroupPids

kill

getContainerId

createContainer

setContainerMaxMemoryLimit

setContainerCpuShares

destroyContainer

collectExistingContainers

getDuccCGroupBaseDir

getSubsystems

cgroupExists

getProcessesOnNode