I continue to have trouble with getting a freshly started server to be responsive. One problem in particular is one that I thought had been resolved some time ago but is apparently biting me right now... With the hdb backend (at least in OL 2.3.34 and OL 2.3.35) if you perform a search with a search base deeper than the root suffix, the search takes a very long time to complete if the cache hasn't been established. In my case the difference is less than a second versus several hours. I'm not sure yet which bit of cache needs to be primed. I can switch back and forth searching with the same filter in the root and then a child search base with the same results.
Have you set DB_CONFIG to reflect reasonable settings given the size of your database?
Is this a bug recursion or something that I just hadn't been noticing? What would be the best search to perform to prepare whatever cache is getting hit to make searches outside of the root DN faster?