App AutoScaler requires a policy file written in JSON with the following schema:
| Name | Type | Required | Description |
|---|---|---|---|
| instance_min_count | int | true | minimal number of instance count |
| instance_max_count | int | true | maximal number of instance count |
| scaling_rules | JSON Array<scaling_rules> | AnyOf |
dynamic scaling rules, see Scaling Rules below |
| schedules | JSON Array | AnyOf |
scheduled, see Schedules below |
| Name | Type | Required | Description |
|---|---|---|---|
| metric_type | String | true | one of system-default metric types memoryused,memoryutil,responsetime, throughput, cpu or user-defined custom metric type |
| threshold | int | true | the boundary when metric value exceeds is considered as a breach |
| operator | String | true | >, <, >=, <= |
| adjustment | String | true | the adjustment approach for instance count with each scaling. Support regex format ^[-+][1-9]+[0-9]*[%]?$, i.e. +5 means adding 5 instances, -50% means shrinking to the half of current size. |
| breach_duration_secs | int, seconds | false | time duration to fire scaling event if it keeps breaching |
| cool_down_secs | int,seconds | false | the time duration to wait before the next scaling kicks in |
| Name | Type | Required | Description |
|---|---|---|---|
| timezone | String | true | Using timezone definition of Java |
| recurring_schedule | JSON Array<recurring_schedules> | AnyOf |
the schedules which will take effect repeatly, see Recurring Schedule below |
| specific_date | JSON Array<specific_date> | AnyOf |
the schedules which take effect only once, see Specific Date below |
| Name | Type | Required | Description |
|---|---|---|---|
| start_date | String,"yyyy-mm-dd" | false | the start date of the schedule. Must be a future time . |
| end_date | String,"yyyy-mm-dd" | false | the end date of the schedule. Must be a future time. |
| start_time | String,"hh:mm" | true | the start time of the schedule |
| end_time | String,"hh:mm" | true | the end time of the schedule |
| days_of_week / days_of_month | Array | false | recurring days of a week or month. Use [1,2,..,7] or [1,2,...,31] to define it |
| instance_min_count | int | true | minimal number of instance count for this schedule |
| instance_max_count | int | true | maximal number of instance count for this schedule |
| initial_min_instance_count | int | false | the initial minimal number of instance count for this schedule |
| Name | Type | Required | Description |
|---|---|---|---|
| start_date_time | String,"yyyy-mm-ddThh:mm" | true | the start time of the schedule. Must be a future time |
| start_date_time | String,"yyyy-mm-ddThh:mm" | true | the end time of the schedule. Must be a future time |
| instance_min_count | int | true | minimal number of instance count for this schedule |
| instance_max_count | int | true | maximal number of instance count for this schedule |
| initial_min_instance_count | int | false | the initial minimal number of instance count for this schedule |
-
If one schedule overlaps another, the one which starts first will be guaranteed, while the later one is completely ignored. For example:
- Schedule #1: --------sssssssssss----------------------------
- Schedule #2: ---------------ssssssssssssss-----------------
- Schedule #3: --------------------------sssssssss------------
With above definition, schedule #1 and #3 will be applied, while scheudle #2 is ignored.