AWSWorkDocsDriveAutoUpdateService pegged at 50% CPU

That service is used to automatically update Amazon WorkDocs Drive when new versions are available. It's no harm to the Workspace instance. But stopping the service will stop updating the files in the WorkDocs drive. The reason it was taking 50% of CPU is likely because there were a lot files to be updated. So I would recommend to leave the service running. If it continues to peg the CPU, please open a support case.