Patent ID: 8515904

Claim:
A method, executed by one or more processors, for performing quota management in a distributed file system comprising: receiving an allocation quota specifying an upper limit of storage available for allocation for a quota set of the distributed file system, wherein the distributed file system includes a first set of one or more metadata file systems storing metadata about files in the distributed file system and a second set of data file systems storing file content data for files of the distributed file system, wherein for at least some files in the distributed file system, metadata for each of the at least some files is stored in at least one of the metadata file systems of the first set and content data for each of the at least some files is stored in at least one of the data file systems of the second set; partitioning, by a coordinator, the allocation quota among the data file systems of the second set, wherein each of the data file systems of the second set is an allocator of storage, wherein each of the data file systems of the second set receives a portion of the allocation quota specifying an upper limit of storage that said each data file system has available for allocation for the quota set; and allocating storage for client requests, wherein said allocating is performed by each of the data file systems of the second set in accordance with the portion of the allocation quota assigned to said each data file system, wherein the portion of the allocation quota assigned to said each data file system specifies an upper limit of storage that said each data file system has available for allocation from the quota set and wherein the portion denotes a total amount of storage that is a sum of a first quantity and a second quantity, said first quantity representing an amount of the first portion currently allocated by said each data file system for the quota set and said second quantity representing a remaining amount of the portion that is reserved space available and provisionally granted to said each data file system for servicing storage requests for the quota set.