There was a DB maintenance scheduled for the panel last night and you may have simply caught it at the wrong time. Given the difference in performance this morning, the maintenance was definitely useful.
The panel is a critical component of managing DH sites and does have some performance issues once in a while (sometimes it's not the panel but communication speeds on the net) but DH is aware of the need and the issues and schedules these maintenance windows to try to address the problem.
Although it seems that issues are becoming more common, a large number (certainly the majority) continue to have no issues at all.
For information about system issues, check out http://www.dreamhoststatus.com
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