• Something; any object place or thing (en.wiktionary.org/wiki/jawn)
• Jawnt, or Joint: Noun that is used in casual conversation to describe any person, place, or especially a thing (list.wikia.com/wiki/Philadelphia_slang)

Now that we’ve gotten the etymology out of the way, we can begin the fusion between the web and it’s jawns until we get the desired result – a whole lotta webjawns.  Now that the enigma has been dissipated, people will sleep soundly, birds will flock, worker bees will work, and we’ll develop web applications and brand new webjawns.

• Minimum version:  PHP 5.3+
• Not backwards compatible
• Improved consistence between componenets
  • __construct() – Constructors will accept options via arrays or Zend_Config
  • Option keys will not use camel caps or uppercase, but instead will utilize lowercase underscore-separated words
• Elimination of most singletons
• Utilization of PHP 5.3 features
  • __invoke() and closures – for use within plugin architecture
  • Namespaces – to help with the super-long class names (Zend_Search_Lucene_Analysis_Analyzer_Common_TextNum_CaseInsensitive comes to mind)
  • goto – to be used when creating Finite State Machines (FSM) and parsers (Zend_Search_Lucene, Zend_Ical, Zend_Markup)
• Autoload-only for all ZF components
• Zend_View
  • Allow optional use of streams for systems where short_open_tags are disabled
  • Automatic escaping of variables
  • Use PluginLoader instead of internal system for managing plugins

There’s a lot of great discussion going on within the official Zend Framework 2.0 Roadmap, as well as a general outline on Zend’s plans, so get over there and read up!

Zend_Search_Lucene_Analysis_Analyzer_Common_TextNum_CaseInsensitive

• Improved LCG entropy (security)
• Fixed safe_mode validation inside tempnam() when… (security)
• Fixed open_basedir/safe_mode bypass in session extension (security)
• Upgraded to PCRE 7.9
• Fixed strip_tags() bug that removed parameters over 1023 bytes even when in exclude list
• Regarding define() and defined()
  • :: was allowed to be included within constant name using define(), issuing a fatal error vs. E_WARNING
  • defined() no longer requires a class to exist when testing class constant
• PHP 5.2.13 Changelog
• PHP 5.2.13 Release Announcement
• Download PHP 5.2.13

• WordPress and Server RAM:  Your (many) Plugin Uses (much) Memory – TPC! Memory Usage driven benchmark of memory used by popular WordPress plugins
• The Answer of X-Factor:  What Your Web Hosting Don’t Want You to Know – Informative article discussing CPU load averages, shared hosting, memory usage, etc.
• Ten Useful WordPress Plugins You May Have Missed – Honorable mention prior to custom checkpoint implementation
• WordPress CMS Review at WebHelper Magazine – Cited as a “key plugin”

If we missed an article, please let us know so we can post it.  Thank you to everyone for your continued support!

Workrave screenshot

RSIs, or repetitive stress injuries, can spell doomsday for a programmer or web developer.  It’s what many of us fear the most; after all, it’s our life’s work, our passion, our love.  I think it is safe to say that pretty much every programmer has felt wrist pain at one time or another.  Many times, it goes ignored, which only worsens the problem.  There is a lot of research in this area, and as a result there are many preventative measures that can be taken to prevent RSIs.

• Ensure your workstation is ergonomically correct in every way.
• Buy a decent ergonomic keyboard.
  • Ergonomic keyboards can be expensive, but often times they will prove to be a worthy investment.  I have been using the Microsoft Natural Ergonomic Keyboard 4000 ($31+) recently, and it has made quite a difference.  Some of the features that have helped tremendously are listed below.
    • Zoom (located between split in keyboard) – in Firefox this works like a scroll wheel, preventing movement from keyboard to mouse
    • Back, Forward (located below spacebar) – go back and forward in your favorite web browser, or cycle through tabs in some programs
    • Quick launch keys – Keys for mail, search, browsing, volume, etc.
    • Favorite keys – Five customizable favorite keys to reduce movement from keyboard to mouse (assign to programs, folders, files, etc.)
• Buy an ergonomic (trackball) mouse.
  • Wrist trouble often begins in the hand or wrist that handles the mouse.  A trackball mouse can limit motion of the wrist; thus, preventing injury.  At the very least, get a mouse that conforms to the natural resting position of your hand where the fingers lay naturally over the mouse buttons.  3M offers a vertical mouse, which seems to have some really good reviews, but I can’t personally vouch for this.
• Eliminate unnecessary movement.  Any items frequently used should be available without having to move at the waist.  The mouse and keyboard should also be close together.
• Take microbreaks every 15 minutes (microbreak = 30-60 second break involving no computer).
• Take five to fifteen minute breaks every hour.  Take this time to stretch, or do something else that will rest your hands, wrists, and eyes.
• Stretch once every hour.
• Download and use Workrave, which will alert you to take microbreaks and rest breaks, and even offers suggestions on different exercises.
• Use voice recognition software.  Windows 7 comes with Speech Recognition out-of-the-box, and it works great for the most part.  If I need a break, or just want to avoid using my hands and wrists, I’ll turn this feature on and let it work its magic.
• Use a touchscreen monitor.  Right now, touchscreen monitors are pretty expensive ($550+ for 19″ LCD touchscreen monitor), but if you have the extra money lying around or really need it, they are available.  There are some conversion kits out there that will convert a regular monitor into a touchscreen, but I can’t say whether or not the quality is there.
• Use automated scripts and macros.  Automated scripts can complete multiple actions at once (such as building an application from source), so you don’t have to.  Macros work off the same concept.

Please feel free to add your own suggestions, and links to any good resources on RSI prevention.  This is an extremely important topic, and ALL programmers need to take these things into account.  It can mean the difference between losing ability to use your hand, and having a high quality of life as an older person.

MySQLTuner (Perl) and MySQL Performance Tuning Primer (Shell) are two scripts that can help diagnose MySQL database performance issues, and provide recommendations on how to solve them.  While both scripts output similar information, the diagnosis can be slightly different with each script, so I like to use both.  Below are directions on how to use them, as well as a few screenshots.

# Download MySQLTuner and MySQL Performance Tuning Primer to ~/scripts.
# To avoid having to invoke Perl/SH each time, make both files executable.
chmod +x ~/scripts/mysqltuner.pl
chmod +x ~/scripts/tuning-primer.sh

# After that, give them a go!
~/scripts/mysqltuner.pl
~/scripts/tuning-primer.sh

Configure Apache, PHP, and MySQL for performance

Make sure that your configuration files are setup correctly for your server, application, and load.  Enough said?

• A HOWTO on Optimizing PHP with tips and methodologies
• HOWTO: Basic Apache performance tuning (httpd)
• HOWTO: Basic MySQL performance tuning (MySQLd)
• Tuning LAMP systems, Part 2: Optimizing Apache and PHP
• Optimize your Apache VPS for WordPress

Best Practices

Did you know that incrementing a class variable is three times slower than incrementing a local variable?  Did you know adding LIMIT 1 to SQL queries for a single row can speed up queries?  Simply changing the way you write code can speed things up considerably.

• 63+ best practice to optimize PHP code performance
• Let’s make the web faster – Google Code
• Top 20+ MySQL Best Practices | Nettuts
• Best Practices for Speeding Up Your Web Site

Get a PHP opcode cache

PHP is an interpreted language, and as such it must be “compiled” into a readable format called opcode.  An opcode cache basically preserves the compiled data, and allows us to essentially skip a step.  This can save much needed resources (CPU, memory, etc.), and lower load time considerably.

• eAccelerator
• XCache
• APC
• Zend Optimizer+

• Custom checkpoints allow administrators to measure memory usage anywhere a WordPress action is available.
• Optional file logging allows administrators to have an effective way of tracking memory usage.
• Improved Security Check, and listed additional variables in System Overview.
• Fixed various bugs (special thanks to those who have taken the time to report issues).

As we continue to improve TPC! Memory Usage and implement new features, we would love to hear your thoughts.  Feel free to leave a message on the official TPC! Memory Usage page.  As always, thank you for your continued support.

Download TPC! Memory Usage

• Additional information can be found at the link below (several plugins are no longer supported, Zend Optimizer compatibility, etc.):
  • http://forums.cpanel.net/f145/php-5-3-now-available-easyapache-141909.html
• All the correspondence leading up to this beautiful moment:
  • http://forums.cpanel.net/f145/php-5-3-x-134377.html

wp-settings.php

Today, I decided to implement a popular distributed caching system called memcached.  Memcached allows PHP objects and variables to be stored in memory, which when used properly, can decrease page load time and server load.  Memcached can also work as a central cache for a cluster of servers.  File-based caching systems work by generating static files, and storing them in a local directory to be served in place of the dynamic content.  This can reduce the number of database queries, and help avoid having to process the script with each new request; however, there is a downside.

Disk-based caching

Disk-based caching systems require information to be pulled from the hard drive, which is often the weakest link in a server.  There have been many improvements in the storage arena, most notably solid-state drives that contain no moving parts, but most servers still use SAS drives.  Storing information in memory can provide a much faster experience, and using memcached can help harness this power.  Some people use file and disk-based caching interchangeably, but they can be slightly different.  File-based caching systems can work with memory, whereas disk-based caching systems always pull from the hard drive.

The native WP_Object_Cache class

WordPress includes a basic caching mechanism, called WP_Object_Cache, that stays alive until a given page (script) has been processed, and sent to the browser via HTTP.  WP_Object_Cache works more like a registry than a caching system, and most database-related functions have a system for utilizing this class.  This can help save time and resources when data is used a multitude of times throughout execution.

When a user views any post, the get_post() function is called.  Before querying the database for the post data, get_post() checks the WP_Object_Cache object to see if the data has been cached.  If false is returned, the database query is completed, and the results are stored in WP_Object_Cache, if successful.  As previously stated, after the page is sent, the information is then flushed from the cache.

Why memcached is sometimes better

Memcached runs as its own service on a server, and can be accessed via PHP by installing a module named MemCache, which is available via PECL.  For the most part, PHP will destroy any information left after executing a script, including the native WP_Object_Cache object.  This means that we have to start all over again when rendering another page, or creating a new request.  The memcached process, on the other hand, is not destroyed when a PHP script is finished executing.  We can store information there indefinitely, or until we are done with it; however, keep in mind that any information stored in memory is lost when the system is rebooted or shut down.

Memcached Object Cache for WordPress

After installing memcached, and activating the Memcached Object Cache plugin for WordPress, load time went down and the average number of database queries was reduced from 25 to 14.  This will prove to be especially helpful as the site grows, as well as during times of high traffic.  Like file, and disk-based caching, memcached also comes with a price.  If memory is scarce, or information only needs to be communicated locally, a disk-based caching system may be better for your application.  The key with this, like anything else in the world of development, is testing.  Try both setups, and get feel for how each system works.  You may find that your original setup was better, or you may be pleasantly surprised with the benefits of memcached.

Installing memcached

WP Memcached Manager

I won’t go into details on how to install memcached on the server, but instead will only focus on the WordPress portion of the installation.  At the bottom of this tutorial, I have included several great links on how to install memcached, and MemCache for PHP on Linux, as well as Windows.  I have personally gone through these tutorials and they work fabulously.

The WordPress part of the installation is very simple.  Follow the directions below:

1. Download the Memcached Object Cache plugin for WordPress.
2. Unzip object-cache.php.
3. Move object-cache.php to /wp-content/object-cache.php.
4. At this point, the Memcached Object Cache plugin has been installed.  If you would like to be able to view the Memcached data inside of the WordPress admin panel, download and install the WP Memcached Manager plugin.  This will also allow you to flush the data via the WP admin panel at any given time.

If you take a look at the new object-cache.php file, you will find that the functions are the same.  WordPress checks for an object-cache.php within the wp-content directory (@see wp-settings.php, line 326 in WP 2.9), and if it exists, the native WP_Object_Cache class file is bypassed.

Further Reading and Downloads

• memcached.org (download latest version)
• PECL MemCache package for PHP (download latest version)
• Installing memcache on Windows for PHP
• Install MemCache on a server running cPanel (1)
• How to install memcached as a service on Linux (2)
• Distributed Caching with Memcached

Other WordPress-Memcached Plugins

• W3 Total Cache
• Batcache

Please feel free to post your experiences, and insight below.  We would love to hear if memcached improved or decreased performance for your blog or application.

• PHP 5.2.12 Release Announcement
• PHP 5.2.12 Changelog

Download PHP 5.2.12