I've been trying to sync for several days with the latest stable build of geth on Ubuntu 16.04
My latest attempt I ran the command as follows, after clearing the db:
geth --rpc --sync-mode=fast --cache=1024
What I've noticed happening is that it will sync to a point, and then arbitrarily restart. For example, the other day it got to a block receipt with a number in the neighbourhood of 3.5 million. At some point I noticed it had all of a sudden went back down to block receipts numbering in the tens of thousands. When I scrolled up through the output there were no error messages or indication of why it would've done this.
This has happened on a couple fresh syncs. Not always in the 3 millions but sometimes in the 1 millions or 2 millions.
It occurred to me that I may be just misunderstanding the output, as the processed states goes up the whole time even when the block receipt numbers suddenly start at 0 again. Any tips would be great.