This version has a number of fixes and improvements:
If your blog is installed in a sub-directory you’ll want to upgrade. This version fixes the mod_rewrite rules that search for the cached files. If upgrading, make sure you delete the Super Cache rules so they’ll be upgraded. (Thanks Otto42)
With a click of a link in the backend page you can view your mod_rewrite rules to check that they are ok. This may help the adventurous who want to upgrade those rules manually too.
The plugin now warns if your blog’s root directory is writeable. Most of the time there’s absolutely no reason for this so it’s good to be reminded to fix it.
Check that $mutex is set. This is really only useful if your server is borked and the filesystem is mounted read-only but it’s good to be complete.
Wondering about the title? Check out this traffic graph Scott Beale posted a few weeks ago and you’ll understand. One of his posts hit the front page of Digg (twice) then Slashdot.org, and was covered by lots of other blogs and media. Wow.
On December 12th our blog hit a record high of 222,523 views in one day.
Version 0.5.1 of WP Super Cache is now available! This release of the plugin will be especially useful for Digg and Slashdot users who experience really huge traffic spikes.
This post has been dugg! Add your Digg here! I doubt it’ll get anywhere near the front page at this stage as it’s only collected 3 diggs in 7 hours. Once it hits 24 hours it disappears forever.
After submitting a site to Digg, some people do the following to get every last ounce of performance out of their WordPress blog, especially on an underpowered server:
Clear the cookies from their browser so the comment form won’t be filled in. (or use a second browser).
Visit the page they submitted to Digg and save it to their desktop.
Open an ftp programme, and recreate the path to the page. Then upload the saved file as “index.html” to that directory.
Finally, after the Digg subsides 24 hours later, remember to remove the directory structure and index.html.
The new version of WP Super Cache automates all the above. You do have to make your blog’s root directory writable by the webserver, but you’re warned continually that this is a major security risk and reminded to make it read-only again.
How does it perform versus the regular static files the plugin creates? In most situations you won’t notice any difference, but when there are tens of thousands of requests hitting your server for one particular page, I find that Apache has trouble keeping up.
In other developments, I added checks for PHP safe_mode. Unfortunately safe_mode stops WP Super Cache working properly. I’m glad to see Mark applied my patch for Subscribe to Comments! No more stray emails if you use the moderation queue to approve comments from many posts!
Compare the following two graphs taken from Google Analytics.
Hits from StumbleUpon
Hits from Digg
At first glance, an appearance on Digg.com looks great! All those lovely hits. 5 times more in a few hours than StumbleUpon sent over a few days. What you don’t see there is the bounce rate. That is the rate at which people visit your site and never come back.
According to Google Analytics, the StumbleUpon bounce rate is 29.94% while a whopping 77.58% of Digg users visit once and leave. I’d rather have the visitor who comes to my site, browses around and then hopefully subscribes.
It’s also easier to gain attention on StumbleUpon and it is likely to continue to send traffic to your site long after your Digg submission disappears into the nether regions of that site never to see the light of day again. That bump on the StumbleUpon graph a few days later was yesterday as people came back into work after the weekend.
In this example, there’s a large difference between the number of visitors Digg and StumbleUpon sent, but StumbleUpon can send you a torrent of traffic too. After I stumbled Grandad’s How to survive your first Guinness post, his site received an extra 16,000 hits plus his subscriber count jumped by a few as people enjoyed what they read.
Update! Grandad sent me a graph of his traffic over the last month. That big spike is the “StumbleUpon Effect”, but the extra traffic afterwards is more interesting. That’s from his new-found regular readers. Glad I could help!
My Super Cache announcement only drew 4686 visitors which is an ultra-light Digg. The Digg page for the post received 808 diggs as of a few minutes ago which is great. Thank you for voting! Judging by the sheer number of comments on that post, there’s a lot of interest out there in the plugin.
What about traffic graphs? The spike at the end of the first graph is my nightly Backuppc service kicking in. The second is from Google Analytics. My server could certainly handle a lot more traffic!
A quick look at my uptime shows the server hardly broke a sweat dealing with the extra traffic except where some idiot spammer bots tried to download my archives a few times. Unfortunately the first time that happened the archives weren’t cached and the load climbed.
Hi, my name is Donncha and I used to have text-link-ads on my blog. They’re gone now but only after Google slapped me into submission and reduced my page rank to 4. Initially I felt angry and shocked that this happened but I have no excuse, I heard it from the horses mouth, I knew it was coming. I was one of those evil unscrupulous demons who manipulated the pagerank of other sites for money. My guilty conscience is somewhat alleviated by the fact that I refused to show a text link ad for a Viagra spammer yesterday morning. Oh well.
Google’s own advertising, Adsense, is still running here, as is Kontera, (leave a comment and you’ll never see them, isn’t that nice?) and the competitive ad filter advice I gave out a few days ago really makes a difference to your bottom line. Just ask Justin!
What’s in store for the future? Keep an eye on this blog. WordPress MU 1.3 is coming real soon now. There are going to be lots more free and GPLed WordPress plugins, including a pretty cool digg proof cache that also works in WordPress MU. Think of it as WP-Cache on afterburner! A couple of sites are already testing it with positive results. I’m watching the access_log roll by on a server as a digg is happening now. Load average is hovering around 1 and the page loads quickly. Sweet.