YARN-4917. Fix typos in documentation of Capacity Scheduler. (Takashi Ohnishi via iwasakims)

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Masatake Iwasaki 2016-04-06 04:00:31 +09:00
parent 30206346cf
commit 500e5a5952

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@ -55,11 +55,11 @@ The `CapacityScheduler` supports the following features:
* **Hierarchical Queues** - Hierarchy of queues is supported to ensure resources are shared among the sub-queues of an organization before other queues are allowed to use free resources, there-by providing more control and predictability.
* **Capacity Guarantees** - Queues are allocated a fraction of the capacity of the grid in the sense that a certain capacity of resources will be at their disposal. All applications submitted to a queue will have access to the capacity allocated to the queue. Adminstrators can configure soft limits and optional hard limits on the capacity allocated to each queue.
* **Capacity Guarantees** - Queues are allocated a fraction of the capacity of the grid in the sense that a certain capacity of resources will be at their disposal. All applications submitted to a queue will have access to the capacity allocated to the queue. Administrators can configure soft limits and optional hard limits on the capacity allocated to each queue.
* **Security** - Each queue has strict ACLs which controls which users can submit applications to individual queues. Also, there are safe-guards to ensure that users cannot view and/or modify applications from other users. Also, per-queue and system administrator roles are supported.
* **Elasticity** - Free resources can be allocated to any queue beyond its capacity. When there is demand for these resources from queues running below capacity at a future point in time, as tasks scheduled on these resources complete, they will be assigned to applications on queues running below the capacity (pre-emption is also supported). This ensures that resources are available in a predictable and elastic manner to queues, thus preventing artifical silos of resources in the cluster which helps utilization.
* **Elasticity** - Free resources can be allocated to any queue beyond its capacity. When there is demand for these resources from queues running below capacity at a future point in time, as tasks scheduled on these resources complete, they will be assigned to applications on queues running below the capacity (pre-emption is also supported). This ensures that resources are available in a predictable and elastic manner to queues, thus preventing artificial silos of resources in the cluster which helps utilization.
* **Multi-tenancy** - Comprehensive set of limits are provided to prevent a single application, user and queue from monopolizing resources of the queue or the cluster as a whole to ensure that the cluster isn't overwhelmed.
@ -67,9 +67,9 @@ The `CapacityScheduler` supports the following features:
* Runtime Configuration - The queue definitions and properties such as capacity, ACLs can be changed, at runtime, by administrators in a secure manner to minimize disruption to users. Also, a console is provided for users and administrators to view current allocation of resources to various queues in the system. Administrators can *add additional queues* at runtime, but queues cannot be *deleted* at runtime.
* Drain applications - Administrators can *stop* queues at runtime to ensure that while existing applications run to completion, no new applications can be submitted. If a queue is in `STOPPED` state, new applications cannot be submitted to *itself* or *any of its child queueus*. Existing applications continue to completion, thus the queue can be *drained* gracefully. Administrators can also *start* the stopped queues.
* Drain applications - Administrators can *stop* queues at runtime to ensure that while existing applications run to completion, no new applications can be submitted. If a queue is in `STOPPED` state, new applications cannot be submitted to *itself* or *any of its child queues*. Existing applications continue to completion, thus the queue can be *drained* gracefully. Administrators can also *start* the stopped queues.
* **Resource-based Scheduling** - Support for resource-intensive applications, where-in a application can optionally specify higher resource-requirements than the default, there-by accomodating applications with differing resource requirements. Currently, *memory* is the resource requirement supported.
* **Resource-based Scheduling** - Support for resource-intensive applications, where-in a application can optionally specify higher resource-requirements than the default, there-by accommodating applications with differing resource requirements. Currently, *memory* is the resource requirement supported.
* **Queue Mapping based on User or Group** - This feature allows users to map a job to a specific queue based on the user or group.
@ -163,7 +163,7 @@ Configuration
| Property | Description |
|:---- |:---- |
| `yarn.scheduler.capacity.queue-mappings` | This configuration specifies the mapping of user or group to aspecific queue. You can map a single user or a list of users to queues. Syntax: `[u or g]:[name]:[queue_name][,next_mapping]*`. Here, *u or g* indicates whether the mapping is for a user or group. The value is *u* for user and *g* for group. *name* indicates the user name or group name. To specify the user who has submitted the application, %user can be used. *queue_name* indicates the queue name for which the application has to be mapped. To specify queue name same as user name, *%user* can be used. To specify queue name same as the name of the primary group for which the user belongs to, *%primary_group* can be used.|
| `yarn.scheduler.capacity.queue-mappings` | This configuration specifies the mapping of user or group to a specific queue. You can map a single user or a list of users to queues. Syntax: `[u or g]:[name]:[queue_name][,next_mapping]*`. Here, *u or g* indicates whether the mapping is for a user or group. The value is *u* for user and *g* for group. *name* indicates the user name or group name. To specify the user who has submitted the application, %user can be used. *queue_name* indicates the queue name for which the application has to be mapped. To specify queue name same as user name, *%user* can be used. To specify queue name same as the name of the primary group for which the user belongs to, *%primary_group* can be used.|
| `yarn.scheduler.capacity.queue-mappings-override.enable` | This function is used to specify whether the user specified queues can be overridden. This is a Boolean value and the default value is *false*. |
Example: