I have a wordpress site and sometimes when logged in to the admin it can be quite slow. I've attached an image to show what i mean. The first request waits for about 8 seconds before anything else happens, a lot of the time that is about 2.5 to 3 seconds wait. Then all of the other requests get blocked for several seconds.
I do have quite a few plugins (26) could this be the reason or is it something else?
What's actually going on here and what I can do to improve it as much as I can?
Update: I've deactivated all of the plugins and activated them one by one. The two that seemed to have the biggest effect was Advanced Custom Fields and Use Google Libraries. Here's what i found.
These are the requests and time to load the index dashboard page according to the net tab of firebug.
With no plugins activated
With all plugins activated
With all plugins activated but the two mentioned above deactivated
If i activate Advanced custom fields
If i deactivate ACF and activate Use Google Libraries