Because of its shared-nothing architecture, each AMP in a Teradata system exclusively controls its own virtual disk space. Therefore, each row is owned by exactly one AMP. That AMP is the only one in the system that can create, read, update, or lock its data. The AMP-local control of logging and locking not only enhances system parallelism, but also reduces BYNET traffic significantly. The following graphic shows how local autonomy provides each AMP (AMP 92 in this example) with total accountability for its own data.