What is "hhvm"
The Hiphop VM (HHVM) is a virtual machine designed to run bytecode compiled just-in-time from the PHP and Hack programming languages. It is currently maintained by Facebook.
HHVM is created as the successor to the PHP Hiphop execution engine for PHP (Hphpc), which is a PHP-to-C++ transposed also created by Facebook. Based on the experience gained and with the goal of solving problems brought by Hphpc, in early 2010, Facebook decided to create a JIT-based PHP virtual machine. The issues associated with Hphpc included its flattened curve for performance improvements, lack of full support for the PHP language, and difficulties related to time and resource-specific development and deployment processes.
Versions and Support
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| LTS Version | Release Date | End of Support |
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| 3.6 | 11 March 2015 | 28 Jan 2016 |
| 3.9 | 14 Aug 2015 | 15 July 2016 |
| 3.12 | 29 Jan 2016 | 30 Dec 2016 |
| 3.19 | 13 abr 2017 | -- -- ---- |
| 3.20 | 07 June 2017 | -- -- ---- |
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