Alexander on Web Development

Updating, administering and programming in your Drupal has never been easier...and fun!

You know that you just got a hung up cron job in Drupal when you try to run cron and Drupal responds with "another cron is being run" or something similar. A similar problem also happens while clearing the cache from the command line using Drush and you get an error that says "bus error". I've found an effective way to resolve these two problems is to:

Upgrading the Drupal admin module to 2.x was easy. What was difficult was "downgrading" it once I figured out it wasn't working as expected ... for whatever reason.

 

How effective are opcode caches?

Here are some blog posts about PHP, Drupal, and opcode cache engine benchmarks:

Recent. Wrote in 2008 by 2bits, a pretty good Drupal consulting firm. Includes all the gory details and even basic intallation instructions.
Tests were performed on Ubuntu Gutsy 7.10 and Drupal 6.3-dev.
http://2bits.com/articles/benchmarking-drupal-with-php-op-code-caches-ap...

Ahh the feeling of success at five in the morning after an all night long geekout with your remote bash command shell. First I managed to install the Varnish reverse proxy on one of my Dreamhost VPS accounts very recently. Now I have managed to install the APC opcode cache for PHP. Gosh I ran into all kinds of problems. Dreamhost uses Debian - but ironically their popular web control panel, which makes the job of server administrators extremely easy - also makes some weird configurations out of every single crucial file in the whole LAMP stack - making following online tutorials more daunting. But I never gave up, I never do.

Now this site alexanderallen.name, and most of the sites hosted on this Dreamhost account are loading ridicously fast. From a typical 7 - 15 seconds load time for the front page, to a sizzling second or less! Now with APC + Varnish properly configured Drupal sites that typically would take up to one minute or more to load completely load as fast as the good ol'e pure HTML pages of the 90's.

Presenting the contendants: APC vs eAccelerator vs XCache vs Memcached

As my client sites uniques increase dramatically every quarter, so do the amout of memory resources they consume; And the monthly web hosting bill. Except for my personal blog, most of the Drupal websites I have developed are crammed full in features because they are online newspapers. Their nature is to consume massive amounts of memory and thus a solution was needed by both my clients and to reduce Drupal's memory footprint. They because they got their reputation hurt everytime Apache responded with Internal Server Errors due to lack of free memory (while not being able to upgrade memory resources due to strict budget limitations). Me because I didn't want to be getting called and interrogated multiple times a day when the servers went down - and oh boy during events like the student strike on Puerto Rico's public university did these servers go down (I guess they were on strike as well!). Does my scenario sound familiar at all? If it doesn't, skip this post. If you are a newcomer to cache engines like I am you will probably find the following useful.