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Multimedia is popular and file sizes grow larger and larger.
Although micro processor is getting powerful today, the overall
performance od systems with massive data will be influenced by
I/O speed. Current file systems, such as MS-DOS, and UNIX, are
not suitable for large files because they only access one block
of data at a time. Suppose the size of a file is 16K bytes and
it is stored on a disk continuously. When a user wants to get
the whole data of this file at once, these systems need to
issue 32 disk requests to get data. It wastes time. Thus, we
build a file server, called Archer, such that it good
performance for large files. Archer adopts contiguous
allocation and disk arrays to improve I/O speed. It is
established on a multiprocessor machine. Thus, clients can
mount more than one Archer servers, which sit on different
hosts. When one host crashes, clients can access data through
another host as no matter happens. Furthermore, current file
systems can communicate with Archer through NFS interface.
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