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diff --git a/site/docs/documentation/Input/AllocationPolicy.md b/site/docs/documentation/Input/AllocationPolicy.md deleted file mode 100644 index 96aacc9c..00000000 --- a/site/docs/documentation/Input/AllocationPolicy.md +++ /dev/null @@ -1,265 +0,0 @@ -Allocation policies define how, when and where a task is executed. - -There are two types of allocation policies: -1. **[Filter](#filter-policy)** - The basic allocation policy that selects a host for each task based on filters and weighters -2. **[TimeShift](#timeshift-policy)** - Extends the Filter scheduler allowing tasks to be delayed to better align with the availability of low-carbon power. - -In the following section we discuss the different allocation policies, and how to define them in an Experiment file. - -## Filter policy -To use a filter scheduler, the user has to set the type of the policy to "filter". -A filter policy requires a list of filters and weighters which characterize the policy. - -A filter policy consists of two main components: -1. **[Filters](#filters)** - Filters select all hosts that are eligible to execute the given task. -2. **[Weighters](#weighters)** - Weighters are used to rank the eligible hosts. The host with the highest weight is selected to execute the task. - -:::info Code -All code related to reading Allocation policies can be found [here](https://github.com/atlarge-research/opendc/blob/master/opendc-experiments/opendc-experiments-base/src/main/kotlin/org/opendc/experiments/base/experiment/specs/allocation/AllocationPolicySpec.kt) -::: - -### Filters -Filters select all hosts that are eligible to execute the given task. -Filters are defined as JSON objects in the experiment file. - -The user defines which filter to use by setting the "type". -OpenDC currently supports the following 7 filters: - -#### ComputeFilter -Returns host if it is running. -Does not require any more parameters. - -```json -{ - "type": "Compute" -} -``` - -#### SameHostHostFilter -Ensures that after failure, a task is executed on the same host again. -Does not require any more parameters. - -```json -{ - "type": "DifferentHost" -} -``` - -#### DifferentHostFilter -Ensures that after failure, a task is *not* executed on the same host again. -Does not require any more parameters. - -```json -{ - "type": "DifferentHost" -} -``` - -#### InstanceCountHostFilter -Returns host if the number of instances running on the host is less than the maximum number of instances allowed. -The User needs to provide the maximum number of instances that can be run on a host. -```json -{ - "type": "InstanceCount", - "limit": 1 -} -``` - -#### RamHostFilter -Returns hosts if the amount of RAM available on the host is greater than the amount of RAM required by the task. -The user can provide an allocationRatio which is multiplied with the amount of RAM available on the host. -This can be used to allow for over subscription. -```json -{ - "type": "Ram", - "allocationRatio": 2.5 -} -``` - -#### VCpuCapacityHostFilter -Returns hosts if CPU capacity available on the host is greater than the CPU capacity required by the task. - -```json -{ - "type": "VCpuCapacity" -} -``` - -#### VCpuHostFilter -Returns host if the number of cores available on the host is greater than the number of cores required by the task. -The user can provide an allocationRatio which is multiplied with the amount of RAM available on the host. -This can be used to allow for over subscription. - -```json -{ - "type": "VCpu", - "allocationRatio": 2.5 -} -``` - -:::info Code -All code related to reading Filters can be found [here](https://github.com/atlarge-research/opendc/blob/master/opendc-experiments/opendc-experiments-base/src/main/kotlin/org/opendc/experiments/base/experiment/specs/allocation/HostFilterSpec.kt) -::: - -### Weighters -Weighters are used to rank the eligible hosts. The host with the highest weight is selected to execute the task. -Weighters are defined as JSON objects in the experiment file. - -The user defines which filter to use by setting the "type". -The user can also provide a multiplying that is multiplied with the weight of the host. -This can be used to increase or decrease the importance of the host. -Negative multipliers are also allowed, and can be used to invert the ranking of the host. -OpenDC currently supports the following 5 weighters: - -#### RamWeigherSpec -Order the hosts by the amount of RAM available on the host. - -```json -{ - "type": "Ram", - "multiplier": 2.0 -} -``` - -#### CoreRamWeighter -Order the hosts by the amount of RAM available per core on the host. - -```json -{ - "type": "CoreRam", - "multiplier": 0.5 -} -``` - -#### InstanceCountWeigherSpec -Order the hosts by the number of instances running on the host. - -```json -{ - "type": "InstanceCount", - "multiplier": -1.0 -} -``` - -#### VCpuCapacityWeigherSpec -Order the hosts by the capacity per core on the host. - -```json -{ - "type": "VCpuCapacity", - "multiplier": 0.5 -} -``` - -#### VCpuWeigherSpec -Order the hosts by the number of cores available on the host. - -```json -{ - "type": "VCpu", - "multiplier": 2.5 -} -``` - -:::info Code -All code related to reading Weighters can be found [here](https://github.com/atlarge-research/opendc/blob/master/opendc-experiments/opendc-experiments-base/src/main/kotlin/org/opendc/experiments/base/experiment/specs/allocation/HostWeigherSpec.kt) -::: - -### Examples -Following is an example of a Filter policy: -```json -{ - "type": "filter", - "filters": [ - { - "type": "Compute" - }, - { - "type": "VCpu", - "allocationRatio": 1.0 - }, - { - "type": "Ram", - "allocationRatio": 1.5 - } - ], - "weighers": [ - { - "type": "Ram", - "multiplier": 1.0 - } - ] -} -``` - -## TimeShift policy -Timeshift extends the Filter policy by allowing tasks to be delayed to better align with the availability of low-carbon power. -A user can define a timeshift policy by setting the type to "timeshift". - -task is scheduled when the current carbon intensity is below the carbon threshold. Otherwise, they are delayed. The -carbon threshold is determined by taking the 35 percentile of next week’s carbon forecast. When used, tasks can be interrupted -when the carbon intensity exceeds the threshold during execution. All tasks have a maximum delay time defined in the workload. When the maximum delay is reached, -tasks cannot be delayed anymore. - - -Similar to the filter policy, the user can define a list of filters and weighters. -However, in addittion, the user can provide parameters that influence how tasks are delayed: - -| Variable | Type | Required? | Default | Description | -|------------------------|-----------------------------|-----------|-----------------|-----------------------------------------------------------------------------------| -| filters | List[Filter] | no | [ComputeFilter] | Filters used to select eligible hosts. | -| weighters | List[Weighter] | no | [] | Weighters used to rank hosts. | -| windowSize | integer | no | 168 | How far back does the scheduler look to determine the Carbon Intensity threshold? | -| forecast | boolean | no | true | Does the the policy use carbon forecasts? | -| shortForecastThreshold | double | no | 0.2 | Threshold is used for short tasks (<2hours) | -| longForecastThreshold | double | no | 0.35 | Threshold is used for long tasks (>2hours) | -| forecastSize | integer | no | 24 | The number of hours of forecasts that is taken into account | -| taskStopper | [TaskStopper](#taskstopper) | no | null | Policy for interrupting tasks. If not provided, tasks are never interrupted | - -### TaskStopper - -Aside from delaying tasks, users might want to interrupt tasks that are running. -For example, if a tasks is running when only high-carbon energy is available, the task can be interrupted and rescheduled to a later time. - -A TaskStopper is defined as a JSON object in the Timeshift policy. -A TasksStopper consists of the following components: - -| Variable | Type | Required? | Default | Description | -|-----------------------|-----------------------------|-----------|---------|-----------------------------------------------------------------------------------| -| windowSize | integer | no | 168 | How far back does the scheduler look to determine the Carbon Intensity threshold? | -| forecast | boolean | no | true | Does the the policy use carbon forecasts? | -| forecastThreshold | double | no | 0.6 | Threshold is used for short tasks (<2hours) | -| forecastSize | integer | no | 24 | The number of hours of forecasts that is taken into account | - - -## Prefabs -Aside from custom policies, OpenDC also provides a set of pre-defined policies that can be used. -A prefab can be defined by setting the type to "prefab" and providing the name of the prefab. - -Example: -```json -{ - "type": "prefab", - "policyName": "Mem" -} -``` - -The following prefabs are available: - -| Name | Filters | Weighters | Timeshifting | -|---------------------|----------------------------------------------|----------------------------|--------------| -| Mem | ComputeFilter <br/>VCpuFilter<br/> RamFilter | RamWeigher(1.0) | No | -| MemInv | ComputeFilter <br/>VCpuFilter<br/> RamFilter | RamWeigher(-1.0) | No | -| CoreMem | ComputeFilter <br/>VCpuFilter<br/> RamFilter | CoreRamWeigher(1.0) | No | -| CoreMemInv | ComputeFilter <br/>VCpuFilter<br/> RamFilter | CoreRamWeigher(-1.0) | No | -| ActiveServers | ComputeFilter <br/>VCpuFilter<br/> RamFilter | InstanceCountWeigher(1.0) | No | -| ActiveServersInv | ComputeFilter <br/>VCpuFilter<br/> RamFilter | InstanceCountWeigher(-1.0) | No | -| ProvisionedCores | ComputeFilter <br/>VCpuFilter<br/> RamFilter | VCpuWeigher(1.0) | No | -| ProvisionedCoresInv | ComputeFilter <br/>VCpuFilter<br/> RamFilter | VCpuWeigher(-1.0) | No | -| Random | ComputeFilter <br/>VCpuFilter<br/> RamFilter | [] | No | -| TimeShift | ComputeFilter <br/>VCpuFilter<br/> RamFilter | RamWeigher(1.0) | Yes | - -:::info Code -All code related to prefab schedulers can be found [here](https://github.com/atlarge-research/opendc/blob/master/opendc-compute/opendc-compute-simulator/src/main/kotlin/org/opendc/compute/simulator/scheduler/ComputeSchedulers.kt) -::: - |