That is an unusually long wait for a criminal case. Civil cases often drag out for years but criminal trials don't typically make it half that long without delays sought by the defendant.

When I worked as an ADA, the longest trial that dragged out while I was there took 3 years and mainly because the defendant knew he was going to have a very bad time in prison and we had enough evidence that no jury would fail to convict him. So he was constantly trying to find creative ways to cause delays.