In computing, the term object-based file system refers to an architectural blueprint for distributed file systems. An object-based file system

File system

A file system is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device which contain it. A file system organizes data in an efficient manner and is tuned to the...

 splits file metadata

Metadata

The term metadata is an ambiguous term which is used for two fundamentally different concepts . Although the expression "data about data" is often used, it does not apply to both in the same way. Structural metadata, the design and specification of data structures, cannot be about data, because at...

 (such as the filename, its size and access times) from file data and stores them on different servers

File server

In computing, a file server is a computer attached to a network that has the primary purpose of providing a location for shared disk access, i.e. shared storage of computer files that can be accessed by the workstations that are attached to the computer network...

. File metadata is stored on metadata servers, the file data is split into so-called objects and stored on object storage servers. The file system client employs metadata and object storage servers to present a full file system abstraction

Abstraction (computer science)

In computer science, abstraction is the process by which data and programs are defined with a representation similar to its pictorial meaning as rooted in the more complex realm of human life and language with their higher need of summarization and categorization , while hiding away the...

 to the users

User (computing)

A user is an agent, either a human agent or software agent, who uses a computer or network service. A user often has a user account and is identified by a username , screen name , nickname , or handle, which is derived from the identical Citizen's Band radio term.Users are...

.

The object-based file system architecture has several advantages:

• The file system client
  Client (computing)
  A client is an application or system that accesses a service made available by a server. The server is often on another computer system, in which case the client accesses the service by way of a network....
  
   accesses file content directly via object storage servers. Metadata servers are only contacted once when the file is opened, thereby eliminating the metadata bottleneck of block-based distributed file systems.
• The size of these objects can usually be configured on per-file basis. This allows the stripe width to be adapted to the access properties of an individual file when the objects of a file are striped
  Data striping
  In computer data storage, data striping is the technique of segmenting logically sequential data, such as a file, in a way that accesses of sequential segments are made to different physical storage devices. Striping is useful when a processing device requests access to data more quickly than a...
  
   across multiple object storage servers.

File systems that follow an object-based architecture include Lustre

Lustre (file system)

Lustre is a massively parallel distributed file system, generally used for large scale cluster computing. The name Lustre is a portmanteau word derived from Linux and cluster...

 and exofs

EXOFS

EXOFS is an object-based file system implemented on top of an external object store.Its name stands for "EXtended Object File System" referring to its use of ext2-based metadataand object storage devices....

.

Sources