If processing of a single batch is bigger than OwnershipTimeout, or processing was stopped and started after OwnershipTimeout is passed, all agents start to receive the task even if one is already working on it. Each time agent ask for a task the task is returned even if cursor split is already requested. but current agent is working on the task, and will split the cursor only after it processed the first batch. First agent takes the task, and star the work. The others receive tasks, and can't use the cursor as it is not splitable and in progress

You will need to increase the ownershipTimeoutMs parameter in the App_Config\Sitecore\Marketing.xDB\Sitecore.Analytics.Processing.Aggregation.config file to resolve the exception:

<param desc="ownershipTimeoutMs" type="Sitecore.Analytics.Core.ConfigurationHelper, Sitecore.Analytics.Core" factoryMethod="ToInt" arg0="180000" />

If the processing of a single batch is bigger than OwnershipTimeout, or processing was stopped and started after OwnershipTimeout is passed, all agents start to receive the task even if one is already working on it. Each time agent asks for a task the task is returned even if a cursor split is already requested. but the current agent is working on the task and will split the cursor only after it processed the first batch. The first agent takes the task and starts the work. The others receive tasks, and can't use the cursor as it is not splittable and in progress

You will need to increase the ownershipTimeoutMs parameter in the App_Config\Sitecore\Marketing.xDB\Sitecore.Analytics.Processing.Aggregation.config file to resolve the exception:

<param desc="ownershipTimeoutMs" type="Sitecore.Analytics.Core.ConfigurationHelper, Sitecore.Analytics.Core" factoryMethod="ToInt" arg0="180000" />