CGroupsHandler.java
/*
* *
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
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* See the License for the specific language governing permissions and
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*/
package org.apache.hadoop.yarn.server.nodemanager.containermanager.linux.resources;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import java.util.HashSet;
import java.util.Set;
/**
* Provides CGroups functionality. Implementations are expected to be
* thread-safe
*/
@InterfaceAudience.Private
@InterfaceStability.Unstable
public interface CGroupsHandler {
/**
* List of supported cgroup controller types. The two boolean variables denote whether
* the controller is valid in v1, v2 or both.
*/
enum CGroupController {
NET_CLS("net_cls", true, false),
BLKIO("blkio", true, false),
CPUACCT("cpuacct", true, false),
FREEZER("freezer", true, false),
DEVICES("devices", true, false),
// v2 specific
IO("io", false, true),
// present in v1 and v2
CPU("cpu", true, true),
CPUSET("cpuset", true, true),
MEMORY("memory", true, true);
private final String name;
private final boolean inV1;
private final boolean inV2;
CGroupController(String name, boolean inV1, boolean inV2) {
this.name = name;
this.inV1 = inV1;
this.inV2 = inV2;
}
public String getName() {
return name;
}
public boolean isInV1() {
return inV1;
}
public boolean isInV2() {
return inV2;
}
/**
* Returns a set of valid cgroup controller names for v1.
* @return a set of valid cgroup controller names for v1.
*/
public static Set<String> getValidV1CGroups() {
HashSet<String> validCgroups = new HashSet<>();
for (CGroupController controller : CGroupController.values()) {
if (controller.isInV1()) {
validCgroups.add(controller.getName());
}
}
return validCgroups;
}
/**
* Returns a set of valid cgroup controller names for v2.
* @return a set of valid cgroup controller names for v2.
*/
public static Set<String> getValidV2CGroups() {
HashSet<String> validCgroups = new HashSet<>();
for (CGroupController controller : CGroupController.values()) {
if (controller.isInV2()) {
validCgroups.add(controller.getName());
}
}
return validCgroups;
}
}
// v1 specific params
String CGROUP_PARAM_MEMORY_HARD_LIMIT_BYTES = "limit_in_bytes";
String CGROUP_PARAM_MEMORY_SWAP_HARD_LIMIT_BYTES = "memsw.limit_in_bytes";
String CGROUP_PARAM_MEMORY_SOFT_LIMIT_BYTES = "soft_limit_in_bytes";
String CGROUP_PARAM_MEMORY_OOM_CONTROL = "oom_control";
String CGROUP_PARAM_MEMORY_SWAPPINESS = "swappiness";
String CGROUP_PARAM_MEMORY_USAGE_BYTES = "usage_in_bytes";
String CGROUP_PARAM_MEMORY_MEMSW_USAGE_BYTES = "memsw.usage_in_bytes";
String CGROUP_NO_LIMIT = "-1";
String UNDER_OOM = "under_oom 1";
String CGROUP_CPU_PERIOD_US = "cfs_period_us";
String CGROUP_CPU_QUOTA_US = "cfs_quota_us";
String CGROUP_CPU_SHARES = "shares";
// v2 specific params
String CGROUP_CONTROLLERS_FILE = "cgroup.controllers";
String CGROUP_SUBTREE_CONTROL_FILE = "cgroup.subtree_control";
String CGROUP_CPU_MAX = "max";
String CGROUP_MEMORY_MAX = "max";
String CGROUP_MEMORY_LOW = "low";
// present in v1 and v2
String CGROUP_PROCS_FILE = "cgroup.procs";
String CGROUP_PARAM_CLASSID = "classid";
String CGROUP_PARAM_WEIGHT = "weight";
/**
* Mounts or initializes a cgroup controller.
* @param controller - the controller being initialized
* @throws ResourceHandlerException the initialization failed due to the
* environment
*/
void initializeCGroupController(CGroupController controller)
throws ResourceHandlerException;
/**
* Creates a cgroup for a given controller.
* @param controller - controller type for which the cgroup is being created
* @param cGroupId - id of the cgroup being created
* @return full path to created cgroup
* @throws ResourceHandlerException creation failed
*/
String createCGroup(CGroupController controller, String cGroupId)
throws ResourceHandlerException;
/**
* Deletes the specified cgroup.
* @param controller - controller type for the cgroup
* @param cGroupId - id of the cgroup being deleted
* @throws ResourceHandlerException deletion failed
*/
void deleteCGroup(CGroupController controller, String cGroupId) throws
ResourceHandlerException;
/**
* Gets the absolute path to the specified cgroup controller.
* @param controller - controller type for the cgroup
* @return the root of the controller.
*/
String getControllerPath(CGroupController controller);
/**
* Gets the valid cgroup controller names based on the version used.
* @return a set containing the valid controller names for the used cgroup version.
*/
Set<String> getValidCGroups();
/**
* Gets the relative path for the cgroup, independent of a controller, for a
* given cgroup id.
* @param cGroupId - id of the cgroup
* @return path for the cgroup relative to the root of (any) controller.
*/
String getRelativePathForCGroup(String cGroupId);
/**
* Gets the full path for the cgroup, given a controller and a cgroup id.
* @param controller - controller type for the cgroup
* @param cGroupId - id of the cgroup
* @return full path for the cgroup
*/
String getPathForCGroup(CGroupController controller, String
cGroupId);
/**
* Gets the full path for the cgroup's tasks file, given a controller and a
* cgroup id.
* @param controller - controller type for the cgroup
* @param cGroupId - id of the cgroup
* @return full path for the cgroup's tasks file
*/
String getPathForCGroupTasks(CGroupController controller, String
cGroupId);
/**
* Gets the full path for a cgroup parameter, given a controller,
* cgroup id and parameter name.
* @param controller - controller type for the cgroup
* @param cGroupId - id of the cgroup
* @param param - cgroup parameter ( e.g classid )
* @return full path for the cgroup parameter
*/
String getPathForCGroupParam(CGroupController controller, String
cGroupId, String param);
/**
* updates a cgroup parameter, given a controller, cgroup id, parameter name.
* and a parameter value
* @param controller - controller type for the cgroup
* @param cGroupId - id of the cgroup
* @param param - cgroup parameter ( e.g classid )
* @param value - value to be written to the parameter file
* @throws ResourceHandlerException the operation failed
*/
void updateCGroupParam(CGroupController controller, String cGroupId,
String param, String value) throws ResourceHandlerException;
/**
* reads a cgroup parameter value, given a controller, cgroup id, parameter.
* name
* @param controller - controller type for the cgroup
* @param cGroupId - id of the cgroup
* @param param - cgroup parameter ( e.g classid )
* @return parameter value as read from the parameter file
* @throws ResourceHandlerException the operation failed
*/
String getCGroupParam(CGroupController controller, String cGroupId,
String param) throws ResourceHandlerException;
/**
* Returns CGroup Mount Path.
* @return parameter value as read from the parameter file
*/
String getCGroupMountPath();
/**
* Returns CGroupV2 Mount Path.
* @return parameter value as read from the parameter file
*/
String getCGroupV2MountPath();
}