A SHORT POST ON DEADLOCK PREVENTION, DEADLOCK AVOIDANCE AND DEADLOCK DETECTION

DEADLOCK PREVENTION
This ensure that at least one of this conditions can not cope by preventing occurrence of a deadlock.

There are four ways to prevent deadlock

• MUTUAL EXCLUSION
  Not require for shareable resources must hold for non-shareable resources.
• COLD MUD
  This must guarantee that when ever a process requests a resources, it does not hold any other resources.
• NO PREMPTION
  If a process that is holding some resources request another resources, that can not be immediately allocated to it, then all the resources currently being hold are released.
• CIRCULAR WAIT
  Impose in total ordering of all resources types and require that each process request resources in an increasing order of enumeration.
  
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DEADLOCK AVOIDANCE

• Simplest and the most useful model requires that each process declare the maximum number of resources of each type that it may need.
• The deadlock avoidance algorithm dynamically ex-ermines the result allocation state to the ensure that there can never be a circular wait condition. Resources allocation state as defined by the number of available and allocated resources and the maximum demands of the processes.
  
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DEADLOCK DETECTION
If the system doesn't employ a deadlock prevention or a deadlock avoidance. An algorithm then a deadlock situation may occur. In those environment the system must be able to provide.

• An algorithm that ex-ermine the state of a system to determine if a deadlock has occurred.
• An algorithm to recover from a deadlock.
  
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