computeEnvironmentOrder

The set of compute environments mapped to a job queue and their order relative to each other. The job scheduler uses this parameter to determine which compute environment runs a specific job. Compute environments must be in the VALID state before you can associate them with a job queue. You can associate up to three compute environments with a job queue. All of the compute environments must be either EC2 ( EC2 or SPOT ) or Fargate ( FARGATE or FARGATE_SPOT ); EC2 and Fargate compute environments can't be mixed.

All compute environments that are associated with a job queue must share the same architecture. AWS Batch doesn't support mixing compute environment architecture types in a single job queue.