Baseline throughput is the sustained data-transfer rate an EFS filesystem can provide without consuming burst credits. In Bursting Throughput mode, it is 50 MiBps per TiB of storage, with a 1 MiBps minimum. section 9.5.2
Storage size controls the baseline: a filesystem of 1 TiB provides 50 MiBps, while 30 TiB provides 1500 MiBps. Filesystems can temporarily exceed this rate through bursting. section 9.5.2
