https://bugs.freedesktop.org/show_bug.cgi?id=34618
--- Comment #19 from peterle@hottemptation.org 2011-03-05 05:17:08 PST --- Downgraded to 2.6.37.2 scrolling okay after suspsend-cycle. Upgraded to 2.6.38-rc7 scrolling slow after suspend-cycle.
I can confirm that pressing any button for some seconds will speed up the terminal output to normal behaviour.
In some situations scrolling gets not immediately slow after resume form suspend, it occour after some seconds. I added a dmesg from 2.6.37.2 as comparsion.