Operation methods of storage devices, and operation methods of storage systems including hosts and storage devices

An operation method of a storage device, the method comprising:

• storing first data in a nonvolatile memory device based on a first stream identifier in response to a first write request, the first write request being received from an external host, and the first write request including the first stream identifier and the first data;
• generating Redundant Array of Independent Disks (RAID) parity data based on second data in response to an RAID enable request and a second write request, the second write request being received from the external host after the RAID enable request is received from the external host, the RAID enable request including the first stream identifier, and the second write request including the first stream identifier and the second data;
• storing the second data and the RAID parity data in the nonvolatile memory device based on the first stream identifier;
• storing third data in the nonvolatile memory device based on the first stream identifier in response to a RAID disable request and a third write request, the RAID disable request and the third write request being received from the external host, the RAID disable request being received after the storing the second data and the RAID parity data, the RAID disable request including the first stream identifier, and the third write request including the first stream identifier and the third data;
• and
• storing fourth data in the nonvolatile memory device based on a second stream identifier in response to a fourth write request, the fourth write request being received from the external host, and the fourth write request including the second stream identifier and the fourth data.

An operation method of a storage system, the storage system including a host and a storage device, the method comprising:

• sending, by the host, a first directive send command including a first stream identifier and a Redundant Array of Independent Disks (RAID) enable indication;
• setting, by the storage device, first RAID information corresponding to the first stream identifier to an enable state in response to the first directive send command;
• sending, by the host, a first write request to the storage device, the first write request including the first stream identifier and first data;
• generating, by the storage device, RAID parity data based on the first data in response to the first write request and the first RAID information being set to the enable state;
• storing, by the storage device, the first data and the RAID parity data in a nonvolatile memory device based on the first stream identifier;
• sending, by the host, a second write request to the storage device, the second write request including a second stream identifier and second data;
• storing, by the storage device, the second data in the nonvolatile memory device based on the second stream identifier in response to the second write request;
• sending, by the host, a second directive send command including the first stream identifier and an RAID disable indication;
• and
• setting, by the storage device, the first RAID information to a disable state in response to the second directive send command.