1. Some info to share: It seems that the statistics plugin can create a huge table. My host told me that s9y_visitors had 698.423 entries and was 100 MB huge. That was the problem which caused my website to be pretty slow lately.
Deleting the statistics plugin solved my problem.
Perhaps others wonder why their website is slowing down as well...
2. A request: I wonder if the comments table could also cause my website to slow down at some point.
I have set the Anti-Spam plugin to moderate most comments and trackbacks. When I get notified of a comment or trackback and I see that it is Spam, then I just ignore them rather than delete them. Therefore the Serendipity Administration Suite tells me that there are more than 1500 comments pending approval.
The Suite can show all those pending approval comments, but there is not a button "Select all". It would be great to be able to mark them all and delete them all at once.
Or perhaps I should not worry about the many pending approval comments?
UPDATE: Stupid me. I just saw "inverse selection" That does the trick. Sorry.