Original author(s) | Emery Berger, Kathryn S. McKinley, Robert D. Blumofe, Paul R. Wilson |
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Developer(s) | Emery Berger |
Initial release | September 29, 1999 |
Stable release | 3.13 / January 1, 2019 |
Repository | |
Operating system | Linux, OS X, Microsoft Windows |
Available in | C++ |
Type | Memory allocation |
License | Apache License v2 |
Website | hoard |
The Hoard memory allocator, or Hoard, is a memory allocator for Linux, OS X, and Microsoft Windows. Hoard is designed to be efficient when used by multithreaded applications on multiprocessor computers. Hoard is distributed under the Apache License, version 2.0.
In 2000, its author Emery Berger benchmarked some famous memory allocators and stated Hoard improves the performance of multithreaded applications by providing fast, scalable memory management functions (malloc and free). In particular, it reduces contention for the heap (the central data structure used in dynamic memory allocation) caused when multiple threads allocate or free memory, and avoids the false sharing that can be introduced by memory allocators. At the same time, Hoard has strict bounds on fragmentation. [1]
Hoard continues to be maintained and improved, and is in use by a number of open source and commercial projects. [2] [3]
It has also inspired changes to other memory allocators such as the one in OS X since February 2008 (first released in Mac OS X Snow Leopard). [4] [5]
C is a general-purpose computer programming language. It was created in the 1970s by Dennis Ritchie, and remains very widely used and influential. By design, C's features cleanly reflect the capabilities of the targeted CPUs. It has found lasting use in operating systems, device drivers, protocol stacks, though decreasingly for application software, and is common in computer architectures that range from the largest supercomputers to the smallest microcontrollers and embedded systems.
In computer science, garbage collection (GC) is a form of automatic memory management. The garbage collector attempts to reclaim memory which was allocated by the program, but is no longer referenced—also called garbage. Garbage collection was invented by American computer scientist John McCarthy around 1959 to simplify manual memory management in Lisp.
Memory management is a form of resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed. This is critical to any advanced computer system where more than a single process might be underway at any time.
Historically, the classic Mac OS used a form of memory management that has fallen out of favor in modern systems. Criticism of this approach was one of the key areas addressed by the change to Mac OS X.
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mtrace
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