--addcheckpoint doesn't seem to work

[abitrolly]

--addcheckpoint parameter doesn't seem to work to speed up synchronization with latest master. I am using --addcheckpoint=510873:0000000000000000005085d3e8518943180dc918ca12c7738ecb30b57a12f16a and synchronization is still incredibly slow.

2018-04-08 23:43:38.561 [INF] SYNC: New valid peer 58.146.165.243:8333 (outbound) (/Satoshi:0.16.0/)
2018-04-08 23:43:38.562 [INF] SYNC: Syncing to block height 517302 from peer 58.146.165.243:8333
2018-04-08 23:43:38.562 [INF] SYNC: Downloading headers for blocks 125274 to 134444 from peer 58.146.165.243:8333
2018-04-08 23:43:38.573 [INF] CMGR: 40 addresses found from DNS seed seed.bitcoin.sipa.be
...
2018-04-09 08:54:34.508 [INF] SYNC: Processed 10 blocks in the last 12.56s (3153 transactions, height 180885, 2012-05-20 10:42:51 +0000 UTC)
2018-04-09 08:54:45.467 [INF] SYNC: Processed 12 blocks in the last 10.95s (2863 transactions, height 180897, 2012-05-20 12:05:00 +0000 UTC)
2018-04-09 08:54:57.185 [INF] SYNC: Processed 17 blocks in the last 11.71s (3402 transactions, height 180914, 2012-05-20 15:10:03 +0000 UTC)
2018-04-09 08:55:07.686 [INF] SYNC: Processed 10 blocks in the last 10.5s (1835 transactions, height 180924, 2012-05-20 16:33:31 +0000 UTC)
2018-04-09 08:55:19.069 [INF] SYNC: Processed 19 blocks in the last 11.38s (2994 transactions, height 180943, 2012-05-20 19:26:39 +0000 UTC)
2018-04-09 08:55:29.135 [INF] SYNC: Processed 20 blocks in the last 10.06s (2804 transactions, height 180963, 2012-05-20 22:39:05 +0000 UTC)
2018-04-09 08:55:39.981 [INF] SYNC: Processed 18 blocks in the last 10.84s (2444 transactions, height 180981, 2012-05-21 01:37:41 +0000 UTC)

[stevenroose]

@abitrolly --addcheckpoint does work. I used it frequently in the recent past.

The problem and the reason why syncing is still slow, is building the UTXO set, which requires a lot of read and write operations for every block.

PR #1168 is an attempt to greatly reduce this issue.

[abitrolly]

Thanks for the heads up. #1045 conflicts and review is a blocker to this issue. Any ideas how to help?

[stevenroose]

Nothing right now. We are just waiting for #1045 to get reviewed and accepted. Then when #1168 gets more material, you can start testing it. But it's not there yet.