• When in a multisite environment, some plugin administration screens and features are only available to super admins. This is usually for security reasons — the Script Manager, for instance, requires unfiltered HTML capabilities.
• A few theme and plugin features are disabled entirely when in a multisite environment. The Semiologic theme's custom CSS feature, in particular, since it would end up shared between sites. The filesystem-based static cache is another example, since flushing is rather resource extensive for larger sites.
• I introduced a few UI tweaks, e.g. in Google Analytics, but nothing that should make anyone feel not at home.
• The Semiologic theme supports the new WP 3.0 custom background handling feature.
• Generally speaking, things continue to work as they did in the past for standalone WordPress installations.

At the risk of repeating myself, I'm NOT recommending to jump on 3.0 when it gets released. It's no big deal if you do, and don't worry if you did. If you haven't yet by the time you read this, it's no big deal either if you don't. I'll probably be waiting until this Autumn.

As a reminder, the updated Version Checker will disable the WP upgrade nag if you're running WP 2.9.2. If you wish to give WP 3.0 a try nonetheless, you'll still be able to do so from the WordPress upgrader (Tools / Upgrade).

Happy blogging!

I've published a batch of theme and plugin updates, for those of you who run test sites that are powered by bleeding edge packages. (This is configurable under Settings / Semiologic API Key when Version Checker is enabled.) There probably will be a round two in a week or so.

The most visible changes in WP 3.0 are a menu editor and the multisite functionality. A lot of dust needs to settle on both of these fronts. Don't get overexcited about the second one: maintaining multiple domains using a unique WP installation is for the technically oriented minds only.

WP 3.0 also introduces less visible but nonetheless massive changes in the post publishing and administration flows. These introduce the potential for custom post types. They additionally work around a series of long standing defects. Sadly, both came at the cost of introducing new potential quirks in plugins — and several of my own plugins did, in fact, break because of them.

Considering the extent of these changes, I'll be avoiding WP 3.0 until this winter. The next Version Checker update will let you do the same at your option: if your site is up to date and running WP 2.9.2, you won't see WP upgrade nags until WP 3.1.1. (You can of course upgrade WP under Tools / Upgrade if you still want to.)

Happy blogging!

Here's a graph (hat tip, the Japan Times) that you may want to give thoughts to, if it hasn't occurred to you yet that this new tablet might make you revisit your business model:

Key changes since early January, on the top of my head:

• The Semiologic theme automatically resets its panels when needed (e.g. after weird series of events when previewing and not enabling the theme).
• It also fixes WP 2.9 thumbnail cropping.
• Cache flush fixes in Smart Links and Widgets.
• Sem Cache fixes for Apache 1.3 servers.
• Version Checker now works around quite a few transport problems in WP.
• It also drops theme/plugin update nags when a manual upgrade occurs.

A whole bunch of other minor tweaks also went in.

If you're interested in testing this all on your Semiologic Pro installation, browse Settings / Semiologic API Key to enable bleeding edge packages. And then Tools / Semiologic to upgrade the theme and the plugins. (Upgrade Version Checker first, so as to use the transport fixes where needed.)

In other news:

• I'm still working on my backend. It's not moving forward as fast as I'd like it to. The parts that are nearing completion are very sexy, however.
• WP 2.9.2 got released. Though I'm sure everyone has upgraded already. (It's not a major security issue, so no need to rush on it if you haven't yet.)
• WP 3.0 is making progress. The update is going to be quite massive, from a code-base standpoint. I'll post more details in a few weeks.

In order to spare Semiologic Pro users the hassle of needing to upgrade their sites several times this week, I had been stalling a theme update and a rather large number of plugin updates until WP 2.9.1, i.e. today. As noted in a previous post, these updates are nearly all related to the new and improved Semiologic Cache 2.0.

I've released the latter too while I was at it. If you had been testing it since it was in beta, be sure to upgrade it before you upgrade WordPress. (I fixed a last minute annoyance earlier today, which made the memcache-based object cache prevent the WP database upgrade from working.)

Unless an urgent issue creeps up, our next stop will be the new back-end. WP 2.9 and Semiologic Cache 2.0 have been keeping me busy in the past weeks, not to mention taking a few much needed days off and rehashing UI ideas all over the place. But, it's making progress here and there. More on this later in the month.

A happy new year to all!

On the bright side, WP 2.9 might be the shortest lived major WordPress release yet. WP 2.9.1 RC1 is officially in the wild, a mere 10 days after WP 2.9. At the time of writing, 23 bugs were fixed; over half of them were major.

When it gets released, I'll feel quite comfortable upgrading this site. So should you.

In other news, a large batch of plugin updates are on the way. They'll be released alongside WP 2.9, so you can upgrade everything at once. As previously noted, nearly all of these updates are optimizations that are related to the coming Semiologic Cache 2.0.

Regarding the new cache plugin, special thanks go to Mark (Golf Guide). He has been doing his very best to break the plugin in the past weeks. I'll be releasing RC1 in the next few days. I'll open a forum thread when I do.

To help out with testing at that stage, toggle Bleeding Edge packages under Settings / Semiologic API Key. Be sure to choose a site with moderate importance, rather than a mere test site; the site needs some traffic for the tests to make any sense, but not so much that you cannot afford it to be quirky until we look into it (which can be minutes or hours).

• One major bug was simply dismissed;
• A related critical bug was only partially fixed;
• A last critical bug (and its child bug) crept in at the last moment.

As a result of this:

• RSS widgets are completely broken on servers that are missing both of iconv and multi-byte string functions;
• The curl transport is broken on some servers with an outdated library. This breaks the WP cron, and with it future posting, pings, etc.

Not all sites are affected, of course. Most aren't, in fact. But for those few who are, the situation is frustrating.

Fixing your site

If you have upgraded your sites to WP 2.9 and are experiencing any of these issues, the fix should be a matter of uploading these three patched files to your site(s):

They go in your wp-includes folder; simply overwrite them as needed.

Please note that the fix to the SimplePie/RSS widget problem merely prevents SimplePie from failing when it's trying to convert UTF-8 into UTF-8. The correct fix would be that your host installs multi-byte string functions or iconv on your server.

Big hat tip to miqrogroove, who took the time to formally diagnose the curl problem, and scribu, who identified where the fatal errors in RSS widgets came from.

Customer reminder

As discussed in a previous post, Semiologic Pro users are advised to wait for WP 2.9.1.

Update: all three bugs are fixed in WP 2.9.1, so we'll be good to go with that release.

The latter disables core upgrade nags for non-bug fix WP releases. Experience has shown, in past years, that major WP releases need about an extra month of testing in the wild to be really stable. You can still upgrade, when WP 2.9 gets released, under Tools / Upgrade. But WP won't nag you into doing so.

Semiologic Cache 2.0 beta is up for grabs. Heaps of other plugins (and the two themes) got updated and are in RC status in the process.

This needs a bit more testing than usual, since I've been filing quite a few bugs on the WP front that related to the new features I implemented. To participate, switch a site or two of yours to use bleeding packages under Tools / Semiologic API Key, mass-upgrade your plugins, and upgrade the theme.

The performance gains are quite significant, to say the least.

For the most part, the plugin updates and the two theme updates are about conditional flushing of caches. For instance, the nav menus cache is no longer flushed if you edit a post without editing its title, caption, or permalink.

Semiologic Cache 2.0 is of course another story. Its previous version was a forked and bug fixed version of the WP Super Cache plugin. No longer.

2.0 was rewritten from scratch and is a completely different animal:

• It requires PHP 5.0 to work; some features (the query cache) require as much as PHP 5.1.
• The niftier functionality is only available on servers with memcached installed. This is not available on shared hosts; but if you're on a VPS host, such as Hub.org, you can take full advantage of it. (I'll get in touch with Marc so that Hub.org users get memcached by default on Premium VPS and above.)
• So-called "Super caching" no longer occurs for non-key pages (i.e. everything except the front page, and singular pages). Semi-static caching takes over for other pages. This allows to expire the super cached pages automatically.
• The semi-static cache can be handled by memcached. This allows sites who live on multiple servers (such as mine) to avoid lags related to the filesystem.
• A query-level cache has been added for sites that use memcached; it significantly speeds things up for logged in users, provided they haven't authored private posts.
• A persistent object-level cache has been added. This speeds things up for much about everyone, by avoiding round trips to the database when none are needed.
• An asset-level cache has been added. It reduces the number of server requests per page by concatenating javascript and css files.
• A gzip-level cache has been added, at the apache level, for servers that support mod_deflate. This significantly reduces the size of the files sent to end-users whose browser support it.

In short, Semiologic Pro users are ready for the new indexing algorithm that Google is going to roll out early next year. As I write this post, the Semiologic Cache plugin combines the benefits of all of the available performance related WordPress plugins, and more.

It's easy to use, too. And error proof — contrary to the previous, WP-Super-Cache based versions.

How it relates to the new back-end is this: I needed a caching plugin that scaled with a WP-based membership plugin, on a site that is load balanced. The former means we get multitudes of users who are potentially logged in on a site; this rules out plugins such as wp-super-cache.  The latter means we cannot use the likes of query-cache, since it's filesystem based.

I haven't tested Semiologic Cache 2.0 with WP Wishlist, from lack of a copy and license. But I 99% expect it to work as is on sites that use it.

Some neat features make it definitely worth the upgrade. I wouldn't jump on 2.9.0, however; especially if you're using plugins that aren't as well maintained as those from Semiologic Pro. There are over 1,000 tickets in total at the time of writing this post, and WP 2.9 introduces some subtle changes in the schema that may break a plugin here and there.

In order to deal with the WP upgrade, I'll be releasing an updated Version Checker in the next couple of days. It'll disable the WP upgrade nagging until WP 2.9.1 is released. (The same for 3.0, 3.1, etc.)

In other news, Semiologic Cache 2.0, which I've yet to start using on this site, but which I've been working on all week, is starting to look very cool. More on this in a later post.