Title:

  Thread-Specific Storage: An Object Behavioral Pattern for
  Efficiently Accessing per-Thread State

Authors:

  Douglas C. Schmidt (schmidt@cs.wustl.edu), 
  Nat Pryce (np2@doc.ic.ac.uk),
  and Tim Harrison (harrison@cs.wustl.edu).

Contact Info:

  Douglas C. Schmidt
  Department of Computer Science
  Washington University
  One Brookings Drive, Box 1045
  St. Louis, Missouri 63130-4899
  (314) 935-4502

Abstract:

  In theory, multi-threading an application can improve performance
  (by executing multiple instruction streams simultaneously) and
  simplify program structure (by allowing each thread to execute
  synchronously rather than reactively or asynchronously).  In
  practice, multi-threaded applications often perform no better, or
  even worse, than single-threaded applications due to the overhead of
  acquiring and releasing locks.  In addition, multi-threaded
applications are hard to program due to the complex concurrency
  control protocols required to avoid race conditions and deadlocks.

  This paper describes the Thread-Specific Storage pattern, which
  alleviates several problems with multi-threading performance and
  programming complexity.  The Thread-Specific Storage pattern
  improves performance and simplifies multi-threaded applications by
  allowing multiple threads to use one logically global access point
  to retrieve thread-specific data without incurring locking overhead
  for each access.

Subject Area: Concurrency.

Keywords: thread, thread local storage, thread-specific storage