I set out to do a full geth chaindata sync on a new Ubuntu 16.04 LTS machine, and after the first 80-90% of the blockchain downloaded quite fast, the sync speed dropped considerably, to the point where I don't think it will ever catch up.
My geth version is: 1.5.3-stable-978737f5
In the last ~20 minutes, I got just 13 blocks:
I1202 12:08:38.699611 core/blockchain.go:1042] imported 1 blocks, 8 txs ( 3.520 Mg) in 14m1.531s ( 0.004 Mg/s). #2469603 [2e8fa979…]
I1202 12:08:40.108563 core/blockchain.go:1042] imported 2 blocks, 15 txs ( 0.253 Mg) in 1.408s ( 0.180 Mg/s). #2469605 [2e8fa979… / 270b9d5e…]
I1202 12:15:49.759161 core/blockchain.go:1042] imported 4 blocks, 25 txs ( 3.962 Mg) in 7m9.565s ( 0.009 Mg/s). #2469609 [7764d5e0… / a2ed5ef4…]
I1202 12:21:11.151912 core/blockchain.go:1042] imported 3 blocks, 31 txs ( 3.879 Mg) in 5m21.392s ( 0.012 Mg/s). #2469612 [a2ed5ef4… / b7a71fbe…]
I1202 12:26:18.290481 core/blockchain.go:1042] imported 3 blocks, 18 txs ( 3.562 Mg) in 5m7.138s ( 0.012 Mg/s). #2469615 [b7a71fbe… / e43f4673…]
It looks like I am on the main ETH chain: {ChainID: 1 Homestead: 1150000 DAO: 1920000 DAOSupport: true EIP150: 2463000 EIP155: 2675000 EIP158: 2675000}
One thing that might be suspicious is that, in the same 20 minutes, geth has done this much IO ...
PID PRIO USER DISK READ DISK WRITE SWAPIN IO> COMMAND
2933 be/4 ethuser 2.28 G 561.04 M 0.00% 5.23% ./geth --cache=2048
... and the disk is spinning constantly, which is strange, given that it only got 13 blocks.
Note: this is a rather powerful machine in terms of CPU/GPU/RAM, and the chain goes to a large HDD (not SSD).
