Initial things to look for when faced with a problem
Common Problems
Bug Reports

Initial things to look for when faced with a problem

Are the PHP and Zend Optimizer versions you are using compatible?
Refer to the Zend Optimizer product page for detailed information.

Are you sure the Zend Optimizer library file is not corrupted?
Confirm that the downloaded tarball/zip file size matches the size appearing on the Zend Optimizer page.
Run the md5 checksum utility on the ZendOptimizer.so or ZendOptimizer.dll files. You can then compare it with the result stored in the md5 checksum file included with your package.

Are you using a clean PHP build?
PHP should either be built from a packaged release or from a clean cvs tree. Alternatively, it can be downloaded as a binary from an authorized source such as php.net, a php.net mirror, or zend.com.

Was the correct platform selected when you downloaded the Optimizer?
For example, if you are running under Linux, perhaps an incorrect libc version was selected.

Are you operating within a "sane" environment? (specific to Unix)
Be sure that dynamic linking is not broken in any manner on your system. You can test this by entering ldd /ZendOptimizer.so.
If the dynamic linking is not broken, output similar to the following will be displayed:


libc.so.6 => /lib/libc.so.6 (0x40027000)/lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x80000000)
(The exact output will vary from system to system.)

Common Problems

Zend Optimizer did not load
The following phpinfo() output was not displayed:
... with Zend Optimizer vX.Y.Z, Copyright (c) 1998-2007 by Zend Technologies.

It could be that...

• PHP was compiled with debug support.
  The phpinfo() output will indicate that ZEND_DEBUG is 'enabled'. Recompile PHP without the debug support.
  
• PHP used the wrong php.ini or the correct php.ini did not include the optimizer directives.
  To identify if the wrong php.ini file was used, run a trace on httpd -X (in the case of Apache module) or on a standalone PHP exec (in the case of cgi) to see which files it tried to open.
  
• The Zend Optimizer directives in the php.ini file are incorrect.
  For example, there may be typos, the path to the optimizer is incorrect, the Zend Optimizer filename was not entered with the correct case, or the directives included extra white space at the beginning of a line or around a '='.
  
• You are working with the wrong web server installation.
  (This will only occur when there are different installations.)

The Zend Optimizer failed to load because PHP complained about unresolved symbol(s).
This most likely was caused by incompatible versions of PHP and Zend Optimizer, see above under the section Initial things to look for.

Bug Reports

Before submitting a bug report:

• Upgrade to the latest version of Zend Optimizer and the corresponding version of PHP.
• Make sure the problem is related to the Zend Optimizer. Try to recreate the problem by working without the optimizer.
• If the problem is related to a particular script (or a series of scripts), try to isolate the source of the problem as much as possible. In particular, try to exclude anything related to the database being used (if any), and make script independent on any external sources.
• Try to play with different optimization levels - does the problem occur in any or all of them?
• Review web server logs and PHP logs for any indication of the problem.

Still sure you have found a bug in the Zend Optimizer?
Please send the bug report to optimizer-bugs@zend.com. Please include the following:

1. Name and version of operating system.
2. Name and version of web server.
3. Content of php.ini.
4. Output of <? phpinfo(); ?>.
   
5. The problem script (if necessary).
6. Any relevant pieces from web server logs and PHP log.

If you think that your case may be of interest to a broad audience, please post it to the Zend Optimizer forum.