'cpu_limit' : 1, # (int) – CPU limit in units of 10^9 CPU shares.
'mem_limit' : 512 * 1e6, # (int) – Memory limit in Bytes.
'cpu_reservation' : 1000, # (int) – CPU reservation in units of 10^9 CPU shares.
'mem_reservation' : 512 * 1e6, # (int) – Memory reservation in Bytes
They should be int (not float)