WP Super Cache

About a month ago I started trying to cut down the page load time on my site, which at that time was running Wordpress + W3TC + APC cache + Rackspace CDN on a dedicated server.

Back then I made a post here outlining the relatively slow time to first byte (~1+ seconds) and start to render time (~2+ seconds) http://www.webpagetest.org/forums/showthread.php?tid=3555&pid=7529#pid7529

Apparently the issue is that W3TC somehow was not caching the database requests as it should be doing and that every page request therefore had to make a lot of calls to the database which slowed TTFB times.

I tried to find a solution to this, even posting about it in Wordpress’ Support Forums (http://wordpress.org/support/topic/w3tc-database-not-cached?replies=4) but sadly there were no replies and I couldn’t get W3TC to cache the page properly, even after spending days reading the support forums and the W3TC installation documents.

Afterwards I sort of gave up and left thing running the way it is.

Today it occurred to me that there is another caching plug-in, that is the WP Super Cache that is less popular than the W3TC. It didn’t offer the same multiple functionalities as W3TC. For instance, I need to install a separate minify plug in (WP-Minify) and a CDN plug in (CDN Sync Tool) where in W3TC these features are all covered.

However to my surprise WP Super Cache works very well and now my TTFB is very fast at around 0.3 seconds (down from ~1.5-1.7 seconds: http://www.webpagetest.org/result/111007_2Z_1TM5H/ ) and the start to render time is now at 0.9 to 1 seconds (down from ~2.5-2.7 seconds).

First View Time from Dulles improved from ~5.5-5.7 seconds to a high 3 seconds now. With repeat views down to 1 seconds and sometimes under 1 second.

At the same time First View Time from London improved to 5.3 seconds (it was around ~8+ seconds before). FYI the server is in Las Vegas.

I’m very happy to report these findings. Anyone else with the same issue I had can give WP Super Cache a try to see if it improves their situation.

Some things are still not working properly with WP Super Cache, for instance I can’t get the minify and CDN feature working together as the css file would not load properly, but for now I’m very happy as the site is loading at a much faster time than before.

That’s great news. Congratulations! Have you also seen an improvement in real-user performance (in Google webmaster tools)? Hopefully the crawler stats also got a lot better with the pages downloading faster.

I really haven’t been using Google Webmaster tools. What should I look for, patrick?

Look at Diagnostics->crawl stats to see the time it takes the crawler to download the pages and labs->site performance to see how long it takes for users to load pages. There’s not nearly as much information as you can get from analytics but it’s there for looking at without having to do anything.

Well this is very new for me, but the crawl stats report gives this:

Time spent downloading (milliseconds)
High 1,490
Average 661
Low 452

As for Labs > Site Performance:
On average, pages in your site take 4.9 seconds to load (updated on Sep 26, 2011). This is slower than 74% of sites

But I guess those are the old load times. I should check again next month.

Yeah, you want to look at the trend lines and see what the “last updated on” date is. It can lag by a week or so but you don’t have to wait for a full month to see it. Don’t pay too much attention to the averages, you want to see if it took a big drop right around when you implemented the fixes.

Yes Patrick, indeed it does.