What's a reasonable DNS response time?

Just recently the response time for my DreamHost-hosted WP site has shot up, with load times in the 5-15 second range. No, it isn’t a plugin issue, as far as I know - I certainly haven’t made any major changes. This is on the East Coast; it isn’t [shouldn’t be] affected by the recent problems in LA. And running WebSitePulse I’m seeing what looks like really slow DNS response:

Website test results

URL tested: http://speakingofclouds.com
Test performed from: New York, NY
Test performed at: 2013-03-28 16:26:38 (GMT +00:00)
Resolved As:
Status: OK
Response Time: 8.838 sec
DNS: 0.085 sec
Connect: 0.007 sec
Redirect: 3.700 sec
First byte: 5.002 sec
Last byte: 0.044 sec
Size: 56318 bytes

Note that 3.7 second redirect time. I’ve run the same test against other DH and non-DH sites, and none of them show this pattern. And yes, DH is the NS for this domain name…

Any thoughts?

Test just now gave a 14 second wait for the redirect (non www to www) followed by another 14 sec wait for response. The excessive wait time is indicative of server-side issues.

Ask Support to check that your fileserver and sqlserver are in the same location, and ask that they restart your Apache service.

Your site is set to use the www prefix, so choose to use it or not and then stick with it in all settings (DH Panel, WP Admin, .htaccess file, etc).

If slow load times persist then request a transfer.

Well, I finally got a response from Support that said “stable, low load”. I.e. nothing. And the problems are even worse this morning (resulting in lost data). I’ll request a transfer.