Trace class:
  Stream class (ID 0):
    Supports packets: Yes
    Packets have beginning default clock snapshot: Yes
    Packets have end default clock snapshot: Yes
    Supports discarded events: Yes
    Discarded events have default clock snapshots: Yes
    Supports discarded packets: No
    Default clock class:
      Name: monotonic
      Description: Monotonic Clock
      Frequency (Hz): 1,000,000,000
      Precision (cycles): 0
      Offset (s): 1,351,530,929
      Offset (cycles): 945,824,323
      Origin is Unix epoch: Yes
      UUID: c19b5ac9-b8e6-4f78-be95-a605d04e34c6
    Packet context field class: Structure (1 member):
      cpu_id: Unsigned integer (32-bit, Base 10)
    Event common context field class: Structure (2 members):
      vtid: Signed integer (32-bit, Base 10)
      vpid: Signed integer (32-bit, Base 10)
    Event class `heartbeat:msg` (ID 0):
      Log level: Debug (line)
      Payload field class: Structure (1 member):
        msg: String