Patent ID: 8972779
Filing Date: 2015-03-03
Classification: G06F

Abstract:
1. A method of calculating parity, comprising: dividing, by a client system, a file which is to be stored into chunks of a preset size, and distributively storing the chunks in a plurality of data servers; sending, by the client system, a data write complete notification message to a metadata server; storing, by the metadata server, a file sent through the data write complete notification message in a recovery queue; sending, by the metadata server, a random data server a parity calculation request for the file stored in the recovery queue; and performing a parity operation by the data server receiving the parity calculation request wherein the performing of the parity operation includes: receiving a request for allocating and calculatinq a parity, chunk containing information regarding a stripe from the metadata server, generating a parity chunk file which is to store parity; allocating a temporary of a chunk size, which is to be used for the parity operation; requesting data for parity calculation from a data server storing a data chunk constituting the stripe, and storing received data in the temporary buffer; storing the data, stored in the temporary buffer, in the parity chunk file when the received data is a first data chunk; performing the parity operetion upon the data read from the parity chunk file and the data stored in the temporary buffer when the received data is not a first data chunk, and storing the data, stored in the temporary buffer, in the parity chunk file; sending a parity reflection complete response to the data server sending the data chunk; and sending a parity calculation complete response to the metadata server when parity operation for every data chunk constituting the stripe is completed.