Intelligent Workload Management (IWM) is a dynamic resource manager that runs as a lightweight control layer in Atlas. IWM is made up of policies that do the following:
Monitor cluster workloads
Respond to traffic spikes, usage changes, and resource contention
Provide automated safeguards to maintain availability under load
IWM policies are load-shedding, meaning they reject, terminate, or delay operations to keep the cluster healthy under overload. When these policies act, your application might see new overload errors or timeouts.
Important
For best results with load-shedding policies, follow the guidance in Overload Errors.
IWM Policies
IWM Policy | Description | Replica Sets | Sharded Clusters | Dedicated Clusters | Flex Clusters | Enabled by default [1] |
|---|---|---|---|---|---|---|
Write-Blocking | Blocks writes on the primary node when free disk space falls below defined thresholds to prevent disk exhaustion. See Write-Blocking. | |||||
Adaptive Operation Rate Limiting | Controls the rate at which MongoDB accepts new operations to protect the server from overload. See Adaptive Operation Rate Limiting. | |||||
Query Sentinel | Protects cluster availability by terminating long-running query operations. See Query Sentinel. |
| [1] | For dedicated clusters running MongoDB 8.3+, Atlas automatically sets enablement for Intelligent Workload Management to Atlas Managed in the Atlas UI. Atlas Managed policies are enabled or disabled by Atlas based on the cluster's MongoDB Server version. If you set Intelligent Workload Management to Enabled or Disabled in your cluster settings, Atlas does not override your selection. |
| [2] | For dedicated clusters running MongoDB 8.0+, Write-Blocking is enabled by default. |
Configuration
To enable or disable IWM, see the IWM settings. If IWM is disabled, Atlas displays a banner in the Atlas UI when IWM would have activated, such as during long-running queries or high operation rates.
Observability
To learn more about how IWM policies affect your workload, see Review Available Metrics and Review Alert Conditions.