Improve WordPress Comments Load time when using Akismet: Adding an index to wp_comments

A customer of mine was seeing a 15 second load time on their WordPress site when clicking on “Comments”.

I installed Query Monitor and saw that the Akismet plugin was running the following SQL command on each comment.

SELECT COUNT(*) FROM wp_comments WHERE user_id = 1820 AND comment_approved = 1;

This query was to show how many comments the user had previously had approved. The query was taking 0.5 seconds per comment listed when you visit the “Comments” page. The page was taking around 15 seconds to load at times. Now if you had this page set to load 100 comments per page, then you’re looking at 60 seconds.

I decided to run an explain on the query to figure out what was going on.

explain SELECT COUNT(*) FROM wp_comments WHERE user_id = 778 AND comment_approved = 1;

Which resulted in the following. (Sorry for the screenshot, copy/pasting and reformatting was not something I wanted to do. Also this references the wp_bspr_comments. This is due to the database having a wp_bspr for it’s table prefix.

MySQL Explain on wp_comments query not indexed

As you can see, the query is having to go through 19866 rows within the wp_comments table which is the total amount in the table. Since they’re using count(*) all rows are scanned.

So I decided to add an index for the user_id and comment_approved columns.

create index wp_comments_askismet ON wp_comments (user_id,comment_approved);

No when running an explain, there are only 9 rows scanned.

MySQL Explain on wp_comments with Aksimet after index

Load times were reduced dramatically. However, this can all be mitigated if you simply turn of the Akismet feature.

Akismet option to show number of approved comments beside each comment author.

0 Shares:
You May Also Like

Mobile Chat When Will it Work?

If you've had an iPhone since the launch of Apples Application Store, then you most likely have bought the app Mobile Chat. I mean who wouldn't, just looking at their features http://mobilech.at/features you'd be silly not to pick the only instant messenger on the iPhone. Granted there are Web App versions, but nothing application wise. Here are some of the features.
MobileChat supports the following protocols: * AIM/ICQ/.Mac/MobileME * Windows Live/MSN * Yahoo Messenger * GTalk * Jabber/XMPP Multiple Accounts

Want a Google Reader equivalent, then check out Tiny Tiny RSS 1.2.12

When I firsted looked at the this application, I thought it was going to look ugly and have no functionallity. I mean after looking at Google Reader and using it for some time, it really was another good Google Application. And it was made to make it easy to read and sort RSS feeds. One look at the demo, and I was hooked. It has some common features that Google Reader does, starred items and labels. I just wonder if you can plop and authentication/user account creation on it so that you can offer your own branded reader similar to Googles. TinyTiny RSS 1.2.12 Demo!
Tiny Tiny RSS 1.2.12 (Default branch) - Screenshot Tiny Tiny RSS is a Web-based news (RSS, RDF, or Atom) feed aggregator designed to allow you to read news from any location, while feeling as close to a real desktop application as possible.
License: GNU General Public License (GPL)
Changes:
This release fixes reported bugs, adds the zh_CN translation, and adds various minor improvements.

[FreshMeat]

Hard times for hard drives: US may ban popular imports

This could be a damaging blow to quite a few companies within the United States. For instance, take a dedicated server hosting company that relies on one of many hardware vendors like Dell or HP (Hewlett-Packard). Its possible that said vendor will have stock pile of hard drives. Put lets put this into perspective. If you read the entire article you will see a similar situation that ended with Broadcom filing a complaint against Qualcomm. The International Trade Commission banned Qualcomm from shipping any new chips and hardware into the United Sates, and any chips that were already being shipped to the United States could continue. The ban lasted for 45 days, until an appeal by Qualcomm was successful and then the ban was lifted.