File system updating metadata of files according to results of keyword search

A storage system comprising:

• an interface for communicating with a client computer via a network;
• a processor;
• and
• a disk device,
• wherein the disk device records one or more files including a file name, data, and an attribute information area in which a registered keyword as metadata of the data is registered,
• wherein the one or more files is written in XML,
• wherein the processor comprises:
• a file access control unit that controls access to the one or more files;
• and
• a file search unit that searches the one or more files,
• wherein the file search unit comprises:
• an attribute information search unit that searches a file of the one or more files by comparing the registered keyword and an input keyword when a keyword to be used in the file search is input;
• and
• an entire document search unit that searches by comparing the entire file and the input keyword,
• wherein when the search by the attribute information search unit cannot produce the file, the search by the entire document search unit is performed,
• wherein the file access control unit comprises an attribute information change unit that stores the input keyword as the registered keyword into the attribute information area the file obtained as a result of the search by the entire document search unit, and stores the input keyword as an important registered keyword into the attribute information area of the file which is opened for a period more than a predetermined period among the files obtained as the result of the search by the entire document search unit, the period being detected by the file access control unit, and
• wherein among the files obtained as the result of the search, the file search unit outputs as a search result the file which has in the attribute information area the same important registered keyword as the keyword input in the search, prior to outputting the other files.