Using Permalinks causing CPU high usage

From an article on AppThemes

If you plan on running a site with hundreds or thousands of posts and you want to ensure it can scale and stay speedy, here are a few rules you should abide by:

Don’t start your permalink structure with the category or postname fields. For example:
/%category%/
/%postname%/
These are the most resource intensive custom permalink structures because they are text fields and at the beginning of your permalink structure. It takes more time for WordPress to distinguish your post URLs from page URLs and needs to store additional meta data in your database.

Select a structure that starts with a numeric field (i.e. the year or post ID) or with a hard-coded base path (i.e. /posts/)
/%year%/%postname%/
/%post_id%/%postname%/
/posts/%postname%/

DB Cache Reloaded is causing issue with WP3.4. See the Master List

@seacoast Web Design : I started using DB Cache Reloaded after the problems started and it’s actually helping.

@shane Gowland : I tried using alternative permalink structures but the problems stay the same. It changes only when I’m using the default, without rewrite rules.

I recently read an article about the impact of using a lot of pages. I’m using 200 pages, but i don’t know what to do with that information, because I can’t simply delete them.

Thanks for your inputs.

How about using “almost-pretty” permalinks? (yoursite.com/index.php?=category/postitle/)

@shane Gowland : The “almost-pretty” permalinks structure doesn’t work either.

I stopped searching into the Permalinks problem, and I’m starting to think that maybe it’s an outside problem. My webhost is kind of bad with delivering informations, so I don’t really have anything to work with, but I’ve just installed Bad Behavior and I’m expecting some results soon. I hope.

I think that the CPU usage is low when I comeback to the default permalinks structure because the thing causing the high is using my pretty links to do so and is kind of lost when they disappear. Maybe my logic is wrong but I found nothing else to help me.

So, I was right in my last message. The High CPU usage was in fact the consequences of bots whom crawl discretely in my DB. I blocked there IPs, problem solve.

Thanks anyway for your help. And now, I close this topic.

That’s really only a temporary solution. Replace the traffic from those bots with legitimate users, and the problem will quickly return. There is still an underlying issue to look for.