Raid reconstruction optimizing method

The invention discloses a raid reconstruction optimizing method. The optimizing method is that a detecting mechanism is added before reconstruction, a raid device and a logical volume mapping table raid_lun_table are searched to detect the part distributed with a logical unit and the part without being distributed with the logical unit in the raid, and the part distributed with the logical unit is reconstructed only. According to the optimizing method, the part distributed with the logical unit is reconstructed only, so that the resource and time consumption in reconstruction of the part without being distributed with the logical unit can be avoided.