I was going to open a new thread on the high CPU issues I've been seeing, but maybe this is the right place, even though I couldn't tie it down to Logs usage.
I've tried installing both the RCs and the released 3.0 64-bit version, in an ESXi VM, and in all cases have seen some form of 100% CPU usage causing a stall and lockout of the Administration interface, at which point I'm never sure if the actions are completed or not. The only way out, I've found is to re-boot.
I've attached a couple of screen shots, to show that these are not just transitory occurrences. The first shows the CPU usage over an hour, showing that the CPU usage is almost constantly at 100%. The dips in the graph are, from memory, when the browser threw the "Script not responding" pop-up. Other than responding to the pop-ups, where I actually could, there was nothing else going on. I was the only user connected.
On the times I have been able to get a "top" running, the processes that appear to be using the CPU are a mix of everything, mostly unexpected, as can be seen in the 2nd screen shot. However, it is definitely Firefox using the most.
Cheers.