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   [1]Indrek's Home  |  [2]Crystal Space  |  [3]SableCC  |  [4]JIT-PHP
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   Indrek's JIT-PHP

   This is another approach to the [5]PHP language compiled script
   caching. I have written this piece by piece through the years. As
   there are already half a dozen products offering similar functionality
   the code has no real strategic or commercial value. But I figured it's
   just as bad leaving it rotting on my hard drive so I decided to clean
   it up and publish to Internet.

   So this software is just provided for your information only. You might
   test it and see how it performs but I have no reason right now to
   start maintaining and perfecting it.
   Download

   The source code is available for download. As it stands there are no
   binary packages avilable. The current version is at 0.1 -
   [6]jphp-0.1.tar.gz. Please read this document or the provided
   [7]README.
   Quality

   The code is definitely not production quality. Although it has been
   debugged reasonably well (using [8]valgrind and stresstesting) it does
   lack real world experience. As you read the license there are no
   warranties.

   The bulk of code has been written using the C++ language. I also made
   heavy use of the C++ STL feature. The code still is not perfect as I
   had no time to refine it and did a few quick hacks. Also in the past I
   lacked many skills as a C++ developer so it can be primitive and have
   some questionable design issues.
   Performance & Optimizations

   JIT-PHP does several optimizations. It encodes the script and applies
   additional optimization to the bytecode. The files are stored on both
   the hard drive and optionally in IPC shared memory segment for extra
   quick access. Also JIT-PHP does its own bytecode execution and has
   extended the process for better speed.

   So the performance of JIT-PHP should match that of other similar
   softwares. When it comes to simple filesystem based caching (not
   shared memory) it should be somewhat faster due to its binary
   approach.

   One of the unique feature of JIT-PHP is that it extends the
   instruction set of PHP language and provides its own execution code
   (modified zend_execute.c from the Zend engine). The performance should
   be close to the [9]Zend(tm) Optimizer product with a few exceptions.

   There is one thing that is a bit slower - calling PHP defined
   functions. This could be optimized of course by resolving the symbols
   at load time.

   The current source code has been tuned to the gcc 3.3. With a bit of
   hacking you should be able to get it to compile on older gcc. In my
   previous tests the gcc 2.95 generated code was around 5-10% faster
   than that of gcc 3.3.

   On a more philosophical note the execution speed is not something
   extreamly important, especially in the business of web sites. Proper
   content management and caching features produce far better results.
   Platforms & Architecture

   The code was developed on a x86 Linux system ([10]SuSE 8.0, 8.2). I
   don't see any inherent reason why it should not run on other x86 based
   UNIX systems. It is inherently tied to the gcc implementation. Notably
   it uses the gcc jump tables to speed up execution.

   There is a binary hack in use (freplace.cc) that is architecture
   dependant. I developed code to implement it on the SUN sparc
   architecture but I have not tested the whole software there.

   Also memory alignment would have to be tuned on more demanding systems
   (data.cc).

   The freplace.cc may also come to problems with memory protection
   systems.
   Compilation & Installation

   You need to have the source distribution of PHP to compile jphp. I
   have tested compilation with php-4.3.1 and php-4.3.2. Edit the
   Makefile and change the PHPTREE variable pointing to the untared php
   source tree. If you are running a weird system you might need to do
   additional hacking - like changing the optimization flags for gcc.

   Type make and hopefully you'll end up with libphpjit.so. Copy it to a
   safe directory and add the following line to your php.ini:
   zend_extension = "/path/to/libphpjit.so"

   There are additional configuration directives available in the file
   [11]CONFIGURATION. Please read it. That's about it.
   Licensing issues

   The code is currently distributed under the [12]Q Public license (see
   the [13]LICENSE.QPL). This disallows you to use this software for
   purely closed commercial purpose.

   The reason is that not only does this software do translation and
   encoding of your scripts - this software also loads, binds,
   interpretes and executes your scripts.
   Links to similar software
     * [14]afterBURNER
     * [15]APC
     * [16]ionCube PHP Accelerator
     * [17]Turck MMCache for PHP
     * [18]Zend Accelerator

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   Copyright © 2001-2003 Indrek Mandre

References

   1. http://www.mare.ee/indrek/
   2. http://www.mare.ee/indrek/crystal/
   3. http://www.mare.ee/indrek/sablecc/
   4. http://www.mare.ee/indrek/jphp/
   5. http://www.php.org/
   6. http://www.mare.ee/indrek/jphp/jphp-0.1.tar.gz
   7. http://www.mare.ee/indrek/jphp/README.txt
   8. http://developer.kde.org/~sewardj/
   9. http://www.zend.com/
  10. http://www.suse.com/
  11. http://www.mare.ee/indrek/jphp/CONFIGURATION.txt
  12. http://www.opensource.org/licenses/qtpl.php
  13. http://www.mare.ee/indrek/jphp/LICENSE.QPL.txt
  14. http://afterburner.bware.it/
  15. http://apc.communityconnect.com/
  16. http://php-accelerator.co.uk/
  17. http://www.turcksoft.com/en/e_mmc.htm
  18. http://www.zend.com/store/products/zend-accelerator.php