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Is it possible to download a recent snapshot of the chainstate database?
I'm running bitcoind (v. 0.11.8) on a machine with ~1mb/s download speed. After my client reached 300000 blocks, the synchronization is going insanely slow. I suspect it's because verification is very slow. The bitcoind processs is using nearly 100% CPU. However, for my purposes I only need a reasonably recent (i.e., up to 30 days old) chainstate database.
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A 30 days old chainstate database does not make sense. Either you have the chainstate completely, and are able to do full validation, or you don't, and you can't validate at all. There is no middle ground of only validating recent transactions, as any transaction you encounter with unknown inputs could either be fraudulent or created more than 30 days ago, and you'll have no way to tell without a full chainstate.
So, either you don't need full validation, and you can use a number of lightweight clients instead, or you do, and you'll either need to build the chainstate yourself by synchronizing history, or copying from a source you trust.
Please don't go download a chainstate from a random place on the Internet though. They can introduce arbitrarily many coins assigned to themselves, and your client would accept them. If many people started running nodes using the same chainstate 'copy' such transactions could even get into blocks, and cause forks in the best case, and theft in the worst case.
I'm working on a prototype/PoC of the protocol client for my thesis. In the long run, the software will run on full blockchain, but first I quickly want to run some performance tests and test the general idea. Believe me, I have analyzed my needs, and ATM a reasonably recent chainstate is all I need. – A. Robertson – 2015-12-02T19:10:05.373
How do you know OP wants to transact? He clearly stated, "for my purposes". Could be "count average block time which isn't provided by blockchain.info" – Tankman六四 – 2017-08-26T12:42:08.327
I can give you a copy if you want to contact me privately. You can find my email address on my website, via my profile. I don't really want to spend the time/bandwidth to keep it public and updated, though. Obviously you can't be sure that I won't try to falsify it, but it sounds like this is just for testing purposes so maybe that's okay. – Nate Eldredge – 2015-12-05T17:07:16.300
@NateEldredge Don't full-node bitcoin clients keep their chainstate database updated automatically? If A. does (did) contact you privately would (did) you just recursively compress the "chainstate" folder and send that to him? I ask because if that's how simple it is, I have an idea to make that concern you mentioned ("you can't be sure that I won't try to falsify it") go away. And if that idea works really well, there could be a lot more validating nodes because they wouldn't need the full blockchain. – Dave Scotese – 2018-10-22T00:00:30.167
Yes, that was my plan. – Nate Eldredge – 2018-10-22T00:02:02.193