Host, storage system including the host, and operating method of the host

A storage system comprising:

• a host;
• and
• a key-value storage device configured to communicate with the host, wherein
• the host comprises:
• at least one processor configured to,
• manage an index based on a tree structure, the tree structure including a plurality of leaf nodes and at least one index node including routing information about the plurality of leaf nodes,
• generate a first log corresponding to a desired leaf node of the plurality of leaf nodes based on an update request, the update request corresponding to a first key-value entry included in the desired leaf node, or generate a second log based on an insertion request for a second key-value entry, the second key-value entry corresponding to the desired leaf node,
• generate a write command, the write command corresponding to the first log or the second log, and
• transmit the generated write command to the key-value storage device so as to store the first log or the second log in the key-value storage device,
• wherein the key-value storage device is configured to store the first log or the second log in response to the write command, and
• wherein the at least one processor is further configured to generate a plurality of keys corresponding to the plurality of leaf nodes, each key of the plurality of keys including a common prefix and an identification of a corresponding leaf node of the plurality of leaf nodes.

An operating method of a host configured to manage an index based on a tree structure, the tree structure including a plurality of leaf nodes and at least one index node including routing information about the plurality of leaf nodes, the operating method comprising:

• generating, using at least one processor, a first log corresponding to a desired leaf node of the plurality of leaf nodes based on a first update request, the first update request corresponding to a first key-value entry included in the desired leaf node, the generating the first log including generating a first new key-value entry, the first new key-value entry including a first value updated based on the first update request as the first log;
• generating, using the at least one processor, a second key-value entry as a second log based on an insertion request, the second key-value entry corresponding to the desired leaf node;
• generating, using the at least one processor, a first write command, the first write command corresponding to the first log or the second log;
• transmitting, using the at least one processor, the generated first write command to a key-value storage device so as to store the first log or the second log in the key-value storage device;
• and
• generating, using the at least one processor, a plurality of keys corresponding to the plurality of leaf nodes, each of the plurality of keys including a common prefix and an identification of a corresponding leaf node of the plurality of leaf nodes.