Media Aware Distributed Data Layout

Abstract

A storage system includes a plurality of vdisks, with each vdisk containing a plurality of storage segments, and each segment providing a specific class of service (CoS). Each vdisk stores files with data and meta data distributed among its storage segments. A storage system includes a memory having multiple classes of service. The system includes an interface for storing a file as blocks of data associated with a class of service in the memory. The interface chooses the class of service for a block on a block by block basis.

1 . A file system for storing a file comprising:
 a plurality of vdisks, each vdisk having a plurality of non-transient storage segments, each segment providing a specific class of service (CoS) for storage, each vdisk having a plurality of inodes stored in an inode table, each inode describing a file in the vdisk, each inode of each vdisk storing data on one or more of a plurality of segments, each segment having a different class of service for storage; and   a controller having a plurality of physical processors which store data of a file in an inode of a vdisk, in one or more segments of that vdisk, each processor serving one or more of the vdisks.   
     
     
         2 . A system as described in  claim 1  including at least one directory storing mappings of file names to (vdisk, inode) pairs. 
     
     
         3 . A system as described in  claim 2  wherein each inode has one or more back pointers to all of the directory entries pointing to the inode. 
     
     
         4 . A system as described in  claim 3  wherein one of the vdisks is a root vdisk. 
     
     
         5 . A system as described in  claim 4  wherein one of the inodes in the root vdisk is a root inode of the file system. 
     
     
         6 . A system as described in  claim 5  wherein each segment has a plurality of chunks. 
     
     
         7 . A system as described in  claim 6 , including an interface to initiate a file system consistency check on an individual vdisk, triggered by an indication of an inconsistency in a specific vdisk. 
     
     
         8 . A system as described in  claim 1  wherein each segment has a plurality of chunks. 
     
     
         9 . A system as described in  claim 8  wherein each segment has chunks added to it dynamically over time. 
     
     
         10 . A method for storing a file comprising the steps of:
 receiving the file at an interface; and   storing data of the file with a controller in multiple segments of one vdisk of a plurality of vdisks, each vdisk having a plurality of inodes, at least two of the Inodes of one vdisk storing data in different segments, each segment having a different class of service for storage.   
     
     
         11 . A method for updating a directory comprising the steps of:
 receiving a request to delete a file, directory or symbolic link at an interface;   creating a first POT entry at a first vdisk server;   sending an operation to a second vdisk server;   creating a second POT entry at the second vdisk server;   sending a response from the second vdisk server to the first vdisk server; and   freeing the first and second POT entries after the completion of the operation.   
     
     
         12 . A method for updating a directory comprising the steps of:
 receiving an object to create a normal file, directory or symbolic link at an interface;   creating a first POT entry at the first vdisk server;   selecting a second vdisk for a new object based upon a predetermined policy;   sending an operation to a second vdisk server;   creating a second POT entry at the second server;   sending a response from the second vdisk server to the first vdisk server; and   freeing the first and second POT entries sometime after the completion of the operation.