I have used Yslow and PageSpeed to find the cause, but I can't seem to figure out why my blog http://www.fotokringarnhem.nl sometimes loads blazing fast (cached files I guess), and other times takes about 10 seconds or longer to load.
I am on a shared server, but haven't had problems like this with other websites on shared servers.
I'm using cloudflare to speed up my blog to speed things up, but to no avail.
Am I missing something?
Pingdom reports of last 30 days (also see http://stats.pingdom.com/hseaskprwiaz):
Edit 1: from basicstate.com
diagnostics
+dns +connect -request -response
So I guess it fails on the requests. Options to narrower it down?
Edit 2:
I used P3 (Plugin Performance Profiler) to determine which plugins caused the most loadtime. Turns out that User Access Manager caused about 60% of load time, so I deleted it.
This did something, I now get way less time outs, but it still takes a long time for anything to popup on the screen.
I used the plugin SQL monitor and determined there are 82 queries being executed on request which takes about 10 seconds!!!!
Use the P3 plugin and use this article to further optimize your website: http://andbreak.com/articles/guide-speed-wordpress/
when all else fails, try switching providers
Edit
Turns out that deleting all automatically saved backups of pages and post as well as the concepts was the key. This dramatically cuts my query time to the server. Now at lightning speeds! Here is the report from the last few days: uptime: 99,21% overall average: 3.322 ms
There is a usefull plugin for WP to also limit the number of autosaves and concepts for posts and pages: Revision control Results weren't instant by the way. Took a day to take effect.
Basicstate results (clearly showing the improvement when I deleted the revisions and concepts on the 11th of 12th (not sure which)).
date uptime dns connect request ttfb ttlb
2012-09-18 98.97 0.031 0.047 0.047 0.353 0.475
2012-09-17 100.00 0.031 0.047 0.047 0.389 0.810
2012-09-16 100.00 0.029 0.045 0.045 0.342 0.499
2012-09-15 93.81 0.029 0.045 0.045 0.739 1.035
2012-09-14 98.97 0.053 0.068 0.068 0.387 0.565
2012-09-13 100.00 0.058 0.074 0.074 0.499 0.853
2012-09-12 95.00 0.030 0.046 0.046 5.994 7.024
2012-09-11 96.97 0.051 0.096 0.096 9.707 9.949
2012-09-10 73.15 0.027 0.043 0.043 6.765 6.952
2012-09-09 43.48 0.027 0.121 0.121 3.652 3.724
2012-09-08 31.82 0.028 0.045 0.045 2.757 2.867
2012-09-07 71.93 0.026 0.042 0.042 5.917 6.091
2012-09-06 60.49 0.027 0.043 0.043 4.590 4.751