What is HHVM? HHVM is an open-source virtual machine designed for executing programs written in Hack and PHP. HHVM uses a just-in-time (JIT) compilation approach to achieve superior performance while maintaining the development flexibility that PHP provides. HHVM supports Hack, PHP 5 and the major features of PHP 7. We are aware of minor incompatibilities, so please open issues when you find them. HHVM also supports many extensions as well.

1. HipHop Virtual Machine
Ratheesh kumar R

2. From this session ..
★ WHO ?
★ FOR WHAT ?
★ STORY BEHIND THE INVENTION
★ CHANCES
★ RISKS
★ REFERENCE
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3. facebook
★ Second largest website in the world.
★ 1.35 billion active users per month.
★ 9000 logins in every seconds.
★ 185 petabytes of data transfer per year.
★ 10-30 million lines of PHP code.
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4. Performance Issues for Facebook
★ Facebook invented there on TCP/IP stack.
★ PHP is an interpreted language.
★ PHP waits for I/O devices,Database,HTTP Response.
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5. Resource issues for Facebook
★ Runs on lakhs of servers.
★ Operational Cost.
★ Maintenance.
★ Space.
★ Employes
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6. First Step in 2008
HipHop Compiler
Transform php into C++
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7. Advantages of HipHop Compiler
★ Having all advantages of a compiled language.
★ Compilation need to be done once.
★ Only need to execute converted binary file.
★ Much faster than normal php execution.
★ Low resource usage.
★ Facebook saved around 10 to 20% of resource usage.
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8. Issues with HipHop Compiler
★ Lost all the advantages of Interpreted Language.
★ Whole code need to compiled every time after a change.
★ 3 to 5 GB of binary code for facebook.
★ Hard to deploy in server.
★ Unhappy developers.
★ Hard to debug.
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9. Second Step in 2010
HipHop Virtual Machine or
HHVM
Just-in-time compiler
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10. What is HHVM ?
★ HipHop Virtual Machine
★ Created by engineers at Facebook
★ New PHP runtime.
★ Translates PHP to Bytecode(HHBC - Hip Hop ByteCode)
★ Just-in-time compiler, turning generated bytecode into machine code.
★ In some cases 5 to 10 times faster than regular PHP
★ No need of Zend Engine
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11. Just-In-Time Compiler
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12. Issues arose then ...
★ PHP is a loosely typed language.
★ Assembly language is strictly typed.
★ Hard to convert PHP to Assembly language.
★ Time taken for Type conversions.
★ Hard to implement a new language other than PHP.
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13. Third Step in 2010
Programming Language for HHVM
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14. Hack Programming Language
➔ Programming language for HHVM.
➔ Evolved from PHP.
➔ If you know PHP,you know Hack.
➔ Hack provides a more predictable PHP.
➔ Statically typed language.
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15. PHP v/s HACK
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16. Issues Solved & Chances of HHVM
★ Better performance.
★ Low resource usage.
★ Hack as the new PHP.
★ Write PHP extensions in PHP.
★ Good for hosting companies.
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17. Risks in HHVM
★ No real open source project.
★ Facebook could loose interest.
★ A community split between PHP and Hack
★ Your favourite extension may not be available.
★ Limited IDE support.
★ Will not support 32-bit operating systems.
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18. Happy people using HHVM
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19. References
http://hacklang.org/
http://hhvm.com/
http://docs.hhvm.com/manual/en/index.php
https://github.com/facebook/hhvm
Google Keywords
Use “HipHop compiler” or “HHVM”
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20. Questions ?
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