SYSTEM FOR COMPRESSING LOG STREAM OF MULTI-SYSTEM ENVIRONMENT

摘要

PROBLEM TO BE SOLVED: To remove an unnecessary data record from a log file even in the case that the last data record is necessary still. SOLUTION: A multi-system log stream in a multi-system environment is compressed. The oldest record required for each system where an entry 210 is written in or erased from the multi-system log stream is traced, and its information is used for compression of a log stream 112. Block IDs 208 corresponding to the oldest records are held in vectors, and it is discriminated whether the entry in a vector substituted before includes the lowest block ID 208 in the vector or not at the time of updating the vector. If it includes it there, all records having block IDs 208 lower than the new lowest block ID 208 in the vector are deleted.