Browse Prior Art Database

File Input/Output Control for Mixed Multimedia and Non-Multimedia Services

IP.com Disclosure Number: IPCOM000116886D
Original Publication Date: 1995-Nov-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 2 page(s) / 48K

Publishing Venue

IBM

Related People

Lett, A: AUTHOR [+2]

Abstract

Disclosed is a method for file I/O control that provides guaranteed data access for time-critical multimedia services while controlling concurrent file access by non-time-critical services which are provided with a guaranteed minimum data rate while using any additional file capacity.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 62% of the total text.

File Input/Output Control for Mixed Multimedia and Non-Multimedia
Services

      Disclosed is a method for file I/O control that provides
guaranteed data access for time-critical multimedia services while
controlling concurrent file access by non-time-critical services
which are provided with a guaranteed minimum data rate while using
any additional file capacity.

      A large file server is required to provide services to both
time-critical multimedia applications and non-time-critical
applications while meeting three requirements
  1.  Multimedia time-critical services receive guraranteed access
  2.  Concurrent non-time-critical services do not cause jitter in
the
       time-critical services
  3.  Non-time-critical service uses all excess file system capacity
       that is not used for multimedia services.

      The disclosed invention focuses on allocation of the buffers
associated with file access as a direct means of satisfying the above
three requirements.  Assume that file I/O is done with large
fixed-size buffers.  A disk device has a capability to perform N
large buffer file I/Os per second, thus having a capacity of R data
rate per second.  To satisfy the first requirement of guaranteed
access for a multimedia file we allocate the number of buffers X to
the multimedia file that satisfy its data rate requirement = X * R /
N.

      All non-time-critical file requests must be handled as a single
request queue.  Then alloc...