I'm having an odd issue with the 7.10 preview system. The time to generate the previews varies wildly. Sometimes it's 10 seconds and sometimes it's several minutes. In some cases the site crashes entirely and has to restart.

It's a pretty complicated site so it takes a few seconds to generate the preview snapshot, but after that it seems to sit there doing nothing for a while. It seems to be worse when the site is under traffic but the Azure instance is not reporting a high consumption of CPU or memory or DB resources. There's nothing in the logs; just a gap during that time when nothing is reported. Has anyone experienced something similar? Thanks.