Methods of provisioning a multiple quality of service file system

Abstract

The invention relates to a multiple QoS file system and methods of processing files at different QoS according to rules. The invention allocates multiple VLUNs at different qualities of service to the multiQoS file system. Using the rules, the file system chooses an initial QoS for a file when created. Thereafter, the file system moves files to different QoS using rules. Users of the file system see a single unified space of files, while administrators place files on storage with the new cost and performance according to attributes of the files. A multiQoS file system enhances the descriptive information for each file to contain the chosen QoS for the file.

1 . A method of provisioning a multiQoS file system on a host, comprising:
 allocating a high QoS VLUN and a low QoS VLUN;   creating file system core structures in the high or low QoS VLUN;   initializing space allocation structures in the high QoS VLUN and the low QoS VLUN; and   creating a fixed table that maps indexes into VLUN identifiers.   
     
     
         2 . The method of  claim 1 , wherein the step of allocating includes computing user capacity required for the high QoS VLUN and the low QoS VLUN. 
     
     
         3 . The method of  claim 1 , further comprising detecting the high QoS VLUN or the low QoS VLUN are running out of space and notifying the file system of the need for expansion of the high QoS VLUN or the low QoS VLUN. 
     
     
         4 . The method of  claim 1 , further comprising adding a new QoS to the file system, allocating a new VLUN at the new QoS, initializing a new space allocation structure in the new VLUN and updating a rule to use the new QoS. 
     
     
         5 . The method of  claim 4 , wherein the new QoS is between the high QoS and low QoS. 
     
     
         6 . The method of  claim 4 , wherein the new QoS is below the low QoS. 
     
     
         7 . The method of  claim 4 , wherein the new QoS is above the high QoS.