Dougal Campbell's geek ramblings | Posts

Server Reconfig

2009-11-13T21:48:13Z

This blog will be moving to a new server very soon. If all goes well, you shouldn’t notice a thing. But just in case, I figured I’d give a warning, so that if you try to visit and you get an error, or the site won’t come up, you’ll know to just come back again later instead of thinking that my site was an early victim of the 2012 apocalypse or something.

I’m doing more than just moving onto a new server though. I’m moving to a new hosting provider, and I’m reconfiguring many aspects of how my services are set up. If you’re interested in the technical nitty-gritty, read on.

Some of you might recall that a little over a year ago, I moved from my original hosting onto Slicehost. I am now moving again, to a service called prgmr.com. I’ve had no problems with Slicehost, but the pricing for prgmr.com is lower, which made it possible for me to expand from 2 servers to 4 servers for less money.

Slicehost VPS hosting is pretty no-frills. You get a server with an initial OS installed on it, and a web-based management tool with some DNS tools and a Java applet console. With prgmr.com, it’s even more no-frills, because the console isn’t web-based. It’s SSH all the way, baby. It’s not for everybody, but it suits me fine. And even though I have more servers, it reduces my monthly hosting costs by about 40%. That said, I’m also reducing my virtual CPU power and disk space a little bit, and Slicehost has multiple facility locations, which might be factors for someone else shopping for hosting. For me, the ability to afford more servers was pretty high up.

So, that said, let’s look at what I’m changing in my setup, and why I felt it was important to move up to 4 servers.

All along, even before Slicehost, I have had trouble dealing with traffic spikes on my web server. I’ve used WP Super Cache and W3 Total Cache. I’ve used XCache for PHP code caching, and for my WordPress object cache. I’ve configured Apache to set caching headers for static files using mod_expires to reduce requests. But I still get load and memory spikes that grind my server into dust. That shouldn’t happen with only 200 visitors per hour (granted, a page view can generate about 50 HTTP requests). Obviously, I’ve configured my server poorly.

Like many large PHP applications, WordPress can be a bit hungry for memory. So when it fights against MySQL and an in-memory object cache for resources, things can start to get dicey. And of course, I’ve got a few other things on the server. When I get hit by a traffic spike (popular article, spammer runs, errant search spiders, etc), memory goes away fast. The machine starts to swap, things get slow, load average spikes as processes begin to wait for resources, and it all snowballs. I’ve got some homemade scripts that keep an eye on things and attempt to restart various services in order to force things back into line, but it’s a pretty heavy-handed way to deal with the problem.

In my new setup, here’s what I’m doing to fix it:

I’ll be running Apache, MySQL, and Memcached all on separate servers, instead of together on one host.
I’m switching from the Apache pre-forking model to the threaded worker model.
I’m switching from mod_php to FastCGI (mod_fcgid) and php-cgi.

There will probably be other tweaks, as well, but those are the biggies. I’m expecting this new setup to handle waaaay more requests than the old one. Oh, and I’m definitely open to any pointers from performance tuning gurus. Please share links and tips!

When the switch-over happens, there might be a period of transition while the DNS changes propagate. I don’t plan to post again until I’ve moved this blog fully to the new host. So you’ll know it’s happened when a new article appears here.

SimpleBits switches to WordPress

2009-10-24T03:49:30Z

Dan Cedarholm, web design guru extraordinaire, has switched his SimpleBits blog to WordPress.

Well, after 6+ years on an ancient and highly customized install of Movable Type 3.15, and 4+ years on various homegrown CMS solutions, I’ve finally upgraded the guts of this site. I chose WordPress. Sure, there are several other excellent options out there to power the blogs of 2010 and beyond, but the familarity of WP, its plugins, pricetag and other factors all fed into the decision. Plus, I told Matt in the halls of SWSW in 2003 that I’d try his little weblog project. I’m finally following through on that.

In addition to running the SimpleBits blog and web design company, Dan is the author of Web Standards Solutions, Bulletproof Web Design, and Handcrafted CSS: More Bulletproof Web Design.

WordPress 2.9 Media Embedding

2009-10-20T19:21:21Z

As promised in my previous post on WordPress 2.9 features, this post will be a demonstration of the super easy media embeds coming in WordPress 2.9. What I find particularly interesting and useful about the new embedding feature, and oEmbed in particular, is that it is truly multimedia. It’s not just about embedding videos. You can embed images, audio, slideshows, or even HTML. Anything that could possibly be included in a web page can be embedded from a remote service via oEmbed.

What’s great about the new media embed feature in WordPress is that it’s so easy to use. How easy? Really easy.

There are two ways to use the new media embedding feature in WordPress 2.9 — raw URLs or the embed shortcode. The first is the simplest — simply include the URL to a page on a supported service on a line all by itself in your post. For our examples, we’ll include a static image from Flickr:

http://www.flickr.com/photos/dougal/3963145416/sizes/s/

Note that this link points to a full web page, not just an image. But with the oEmbed support, WordPress will be able to find out what it needs to fetch, and how to embed it properly in your content. When the post is rendered in the browser, the image will be fetched in place of the URL:

Note that even though the URL pointed to the ’small’ version of the image, the embed gave us the ‘medium’ size instead. This is what Flickr considers the ‘canonical’ version of the image. That might be something to keep in mind. Other services might detect which version of a resource you are embedding and serve up an appropriate version, or Flickr may change this behavior in the future. The important thing here is that all we did was put the URL on a line by itself in our post, and WordPress magically figured out what to do.

Using the embed shortcode is just about as easy. Simply wrap the shortcode around the URL:

[embed]http://www.flickr.com/photos/dougal/3963145416/sizes/s/[/embed]

Which will embed into your post like so:

That worked exactly like the first example, huh? So, if it’s so easy to embed something using a raw URL, why use the embed shortcode? Because it allows parameters! Let’s say you want to put that picture in your post, but you need it to be a particular size, so that it fits into your theme layout better. Simply specify the size inside the opening embed shortcode.

[embed width="200"]http://www.flickr.com/photos/dougal/3963145416/sizes/s/[/embed]

Which will give us the 200px wide image like this:

Another advantage of the shortcode is that you can wrap other HTML around it. For example, on this site, I sometimes put an image inside a div with a class of pull-quote, which results in a highlighted section which floats to the right of the surrounding text (you have to switch from the Visual editor to the HTML editor for this). The code would typically look something like this:

<div class="pull-quote"><img src="/pics/Chocolatebunnies.jpg" /><p>Funny Bunnies</p><div>

I can do the same thing with an embed using the shortcode so that this:

<div class="pull-quote">[embed width="200"]http://www.flickr.com/photos/dougal/3963145416/sizes/s/[/embed]<p>Matt and Dougal at WordCamp Birmingham 2009</p><div>

Gives us the floated, highlighted area that I want:

Matt and Dougal at WordCamp Birmingham 2009

So there you go, a quick example of how to use the new embed features in WordPress 2.9. I was going to mix things up with embeds from different sites, but not all of the oEmbed services listed were working right for me. I might need to do some testing and file some bug reports later.

WordPress 2.9 Features

2009-10-17T19:27:00Z

This site is now running on WordPress 2.9-rare (which is our “pre-alpha” designation, for those of you who don’t know). WP 2.9 is in “feature freeze”, which means no new features will be considered for this version, and the developers will concentrate on finishing up the existing new features and any outstanding bugs. So far, it appears that all of my plugins are working just fine.

The main new features I’ve actually seen so far are the addition of the “Post Thumbnail” box in the writing screen, the new “trash” status for posts, pages, and comments, and the image editor in the Media Library. The image editor lets you do some simple manipulation such as flipping, rotating, scaling, and cropping an image.

If you would like to help out with testing WP 2.9, read the new post on the Dev Blog, Getting involved with the 2.9 beta testing, which will point you to the WordPress Beta Tester plugin. As the post says, don’t do this on a production site that can’t live with possible breakage — here be dragons!

That said, here is a partial list of new features coming in WordPress 2.9:

Post Thumbnails: add an image to be automatically displayed with the post in various views (main page, archives, etc.). The WordPress logo on this post is added with this feature, plus a filter I added to my theme’s functions.php file.
“Trash” status: deleted items such as posts, pages, and comments now go to the “trash”, and can be recovered later, much like delete files in most modern operating systems.
Image editing: basic image manipulation for your media library. You can rotate, flip, resize, and crop images.
Widgets outside of sidebars: there is a new template tag called the_widget(), which allows you to put a widget anywhere in your theme. Oops. As pointed out in the comments, this was actually in 2.8. I had an old message still flagged and didn’t notice the date when I was making this list.
Comment metadata: plugins and themes can now take advantage of arbitrary metadata for comments, just as for posts, pages, and users. This should make it easier to create plugins to highlight “popular” or “hot” comments, among other things.
Custom post types: general support for post types other than ‘post’, ‘page’, and ‘attachment’. This plus the custom taxonomy support we already have will go far to address those to like to claim that WordPress is not a ‘real’ CMS. We’ll be able to organize content in ways that I can’t even think of right now (I need more time to brainstorm).
Media Embeds: I haven’t had a chance to look over this all the way yet, but it’s basically Viper’s Video Quicktags folded into core (minus the editor buttons at this time), including support for the oEmbed standard. With oEmbed, you can just paste in the URL for a page containing embeddable media, and it can auto-detect the proper way to embed it in your post. Supported services so far appear to be YouTube, Google Video, PollDaddy, and DailyMotion. Plus, theoretically, any service that supports oEmbed, which currently includes YouTube, Flickr, Vimeo, Viddler, Qik, and Hulu, among others (according to the oEmbed site). Whoah, awesome! I’ll post a demo of this soon, but you can read Viper007Bond’s post now for more details.
register_theme_directory(): plugins can now add additional theme directories to be searched. This means that a plugin can basically come bundled with its own themes. I’ve already got a project that’s been on the back-burner that can use this feature. I think we might seem some nifty uses appearing in the future.

There will be other things, of course. For example, there are some optimizations to combine a lot of backend management code for post and pages, to eliminate some code duplication and streamline things a bit. But the features listed above are the ones that really stand out, and caught my eye.

So there you have it: a quick rundown of some of the new features coming in WordPress 2.9. There’s some interesting stuff in there. I’m sure we’ll see people using things like post thumbnails, widgets anywhere, and media embeds right away. And I think we can expect a slew of new plugins to take advantage of new features like comment metadata, custom post types, and the new theme directory support.

Which new feature are you most excited about? Is there something you know about that I didn’t mention here? Mingle, discuss!

WordCamp Birmingham 2009 Recap

2009-10-12T19:21:47Z

This post is about two weeks late, but I still wanted to share my notes about WordCamp Birmingham 2009. Short version — it was awesome!

As mentioned previously, I gave a presentation on Jumping into WordPress Plugin Development. When I arrived in Birmingham on Friday night, I still only had a little over half of my presentation notes done, and the rest was still just an outline. I stayed up all night finishing my notes and quickly putting them into a Keynote presentation (which I then exported in several other formats and saved to a USB thumbdrive for safekeeping). I got about two hours of sleep, then I headed over to Innovation Depot.

Saturday

Setup was running a little behind schedule, but I put the extra time to good use by drinking lots of coffee, sampling an excellent red velvet cake muffin, and chatting with some old friends. Eventually, it was time for presentations to begin, and I was one of the presenters in the first time-slot (there were two tracks, nominally “beginner” and “advanced”, or perhaps “social/marketing” and “technical”). I was surprised to see that the room I was supposed to be using fill up past capacity, so we had to quickly relocate to a larger space (and even that room was pretty full). We finally got my laptop hooked to the projector, and I began my talk, about 20 minutes behind the planned schedule.

I won’t recap my talk here, since the slides are available, and I’ll be expanding it into a more detailed set of articles later. But I will say that I was surprised (pleasantly so) at the large turnout. There were about 180 attendees this year, and I think about 2/3 of them attended my session (the other session was a comparison of “wordpress.org” vs “wordpress.com”). I felt like I did a pretty good job presenting, despite my total lack of preparation, but I wasn’t really sure how I did until later, when several people were kind enough to compliment me. Whew, that was a relief!

After my presentation was done, the lack of sleep and the adreneline caught up with me. I wanted to attend several other sessions, but I was in a weird state of tired and keyed-up at the same time, and I was having a hard time paying attention to much. I did sit in on Jeremy Flint’s session on Essential SEO and Analytics for WordPress, and I poked my head in on a couple of others, like Sarah Cannon’s WordPress and Your Brand, and Mitch Canter’s talk on WordPress Security.

Lunch was provided by Dreamland BBQ, which has been a long-time favorite barbecue joint for my family. This was also important because Matt Mullenweg was our special guest, and (being from Texas) he always has to judge the local BBQ selection. Once everyone had gotten a chance to eat, Matt began his keynote.

Actually, Matt did less of a keynote, and more of a “Town Hall” session. He talked about how the community defined WordPress, and surprised me by calling me up to the front. A few of you reading this might not know that I was on the original core development team for WordPress, back in 2003-2004. Also, if you’ve ever looked at the bottom of the “Writing Settings” page in your WordPress admin, seen the “Update Services” section, and wondered what the heck a Ping-O-Matic is, you can thank Matt and me for that. I had created the ping service for myself just for kicks, but then Matt and I branded it as the Ping-O-Matic, launched it to the public, and made it the official ping service for WordPress. Anyhow, Matt and I had worked together on WordPress and Ping-O-Matic, had communicated by email, IRC, IM, and phone for the last six years, but had never met in person until this WordCamp. But I digress.

After Matt talked about community and software freedom for a bit, he opened the floor for questions. Mostly there were questions about what’s upcoming in the next couple of WP releases — the image editor, custom post types, and the merging of WordPress-MU with the main core. After the Q&A, sessions resumed.

Later in the afternoon, we closed the day out with our other keynote speaker, Esra’a Al Shafei, AKA Mideast Youth. She spoke passionately (yet surprisingly upbeat) about how she became involved in efforts to promote political and religious tolerance in the nations of the Middle East. In particular, her efforts have largely centered around bloggers who have been jailed (and sometimes tortured and killed) for publicly disagreeing with something their governments had expressed or done. WordPress comes into the picture because it enabled her to very quickly create web sites as rallying points to bring awareness to the plight of the various people and causes she needed to champion.

After we wrapped up the first day of WordCamp, there was a speaker’s dinner (Thai food) followed by a social pub gathering. Because I was so exhausted, I only planned to stick around briefly. But after I started talking with Matt and everyone else there, I ended up staying much later than intended. Eventually, however, I dragged myself away for some much-needed sleep.

Sunday

The second day of WordCamp took place at Shift Workspace, a new co-working space in Birmingham (with very good pricing, if you’re looking). Instead of speaking sessions, this was a more social day, intended more for personal networking. It was loosely broken into roundtable discussions on whatever topics people decided to talk about and a “Genius Bar”, where you could seek help on particular questions from WordPress experts. Later, there was an impromptu demo and comparison between Flutter and Pods CMS, two WordPress plugins which offer CMS functionality similar to that provided by the CCK and Views modules in Drupal.

Lunch was next door at Rogue Tavern, which opened up exclusively for us WordCamp attendees. I had a fried zucchini and olives appetizer, salad, and mini crabcake sandwiches, all of which were delicious. Everyone else seemed to enjoy the other selections, too. Alas, I knew I was going to be driving back to Atlanta soon, so I didn’t sample any brew. I did get to chat with Matt again before I left, and I hope I’ll be able to touch base with him again in the future.

Photos

Sorry about the poor quality, but my 1st generation iPhone doesn’t take the best pictures. Here are a few shots I got with my camera, mostly from Sunday. You can find many more (and better) pictures in the WordCamp Birmingham Group on Flickr.

Links

Here are some links to other recaps:

Jumping into WordPress Plugin Development presentation

2009-09-26T20:09:31Z

Despite an extreme lack of sleep, I managed to make it through my WordCamp Birmingham presentation this morning on Jumping into WordPress Plugin Programming. I didn’t feel as prepared as I wanted to be, but several people gave me some kind comments, so I guess it must have gone okay. Here is the slideshow I used, which I’ve uploaded to SlideShare (where you can also find my presentation from last year).

Jumping Into WordPress Plugin Programming

View more documents from Dougal Campbell.

Obviously, with the slideshow, you don’t get the extra patter and commentary (did anybody record audio?), but the essential pieces are there. When I can find time (heh), I plan to turn this into a series of articles here on my blog, where I will go into much more depth, and give more complex and useful examples.

Jumping into WordPress Plugin Development presentation

Getting ready for WordCamp Birmingham 2009

2009-09-25T20:40:11Z

In a short while, I’ll be leaving Atlanta, and heading west to Alabama for WordCamp Birmingham 2009. I’m giving a presentation on Saturday morning about Jumping Into WordPress Plugin Programming. Of course, my presentation still isn’t done, so I’ll be burning the midnight oil tonight, finishing up my notes, gathering up my bookmarks, and turning it all into a slideshow. Unfortunately, my presentation is in the first slot of the morning. Fortunately, once that’s over with (for better or worse), I can enjoy the rest of WordCamp relatively stress-free.

Mainly, I’m looking forward to talking to people, both the people I’ve met before, like Mitch Canter of StudioNashvegas, and those I haven’t, like Matt Mullenweg of…everything. If you see me wandering around, feel free to introduce yourself. I might be brain-dead from lack of sleep, and not the best conversationalist, but I’m usually more than happy to talk about WordPress, programming, or other general geekery.

It’s Talk Like a Pirate Day again!

2009-09-21T16:42:27Z

Ahoy, me maties!

Yes, it’s Talk Like a Pirate Day once again. And as customary, my blog is piratified by my Text Filter Suite plugin. For today, all the writing will be automatically translated into pirate speak. If you leave comments, you don’t have to go out of your way to talk pirate, just write normally, and the filters will take care of things for you.

Yaaarrr!

It’s Talk Like a Pirate Day again!

Most Useless iPhone 3.0 Feature

2009-09-06T04:41:24Z

In the iPhone OS 3.0 update, there were a lot of nice features added. Some of them are fairly major and useful, like cut-and-paste. Some of them are subtle and useful, like the 30-second rewind button when playing a podcast. But there’s one feature that sticks out to me as totally useless: “Shake to Shuffle”.

I guess there’s some tiny “cute-factor” to it. But in practical terms, it’s pretty darned useless. When you’re using your iPhone or iPod Touch to listen to music, you’re probably either: on the move (in your car, jogging, biking, mowing your lawn, etc.) or in a passive environment (working at a desk, connecting your iPhone to an external amplifier/speaker system, etc). Rarely are you going to be carrying your iPhone in hand, but still enough to avoid accidental shuffling.

And accidental shuffling is what makes this feature so useless. I didn’t realize that Apple had defaulted this feature “on”. So imagine my confusion when on a couple of occasions I was driving down the road and my iPhone skipped the the next track in the middle of a song. I didn’t think much about it at the time, but then somebody mentioned “shake to shuffle” on Twitter, and it suddenly occurred to me that I should check that setting. Doh!

Thanks, Apple. You re-invented the Sony Discman.

Checking Your WordPress Security

2009-09-06T03:22:13Z

You may have already heard that sites running out-of-date versions of WordPress have been under attack (Lorelle, Weblog Tools Collection, WordPress Dev Blog). Of course, sites running the latest version of the software seem to be safe, which once again takes us back to what I said over a year ago: Upgrade or else! I haven’t seen complete details yet about how this new worm works, but reports say that part of the hack is to create a new Administrator level account, and then try to hide the existence of that account (via javascript) when you view your list of users.

If you want a sure-fire way to make sure there are no “extra” administrator accounts registered in your blog, I suggest going straight to the source: your MySQL database. The following SQL query, run against your WordPress database will show you all users who have the Administrator role:

SELECT u.ID, u.user_login
FROM wp_users u, wp_usermeta um
WHERE u.ID = um.user_id
AND um.meta_key = 'wp_capabilities'
AND um.meta_value LIKE '%administrator%';

Advanced users can run this directly in the command-line MySQL client, or you can do it from phpMyAdmin by selecting your WordPress database and then going to the ‘SQL’ tab to run the query. If you use something other than the standard ‘wp_‘ prefix for your table names, make the appropriate change in the query (three occurrences).