Message-Id: <1491516747.3791700.936828232.69F82904@webmail.messagingengine.com>
From: Tomas <tomas@tomasvdw.nl>
To: Bitcoin Dev <bitcoin-dev@lists.linuxfoundation.org>
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Date: Fri, 07 Apr 2017 00:12:27 +0200
Subject: [bitcoin-dev] Using a storage engine without UTXO-index
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I have been working on a bitcoin implementation that uses a different
approach to indexing for verifying the order of transactions. Instead of
using an index of unspent outputs, double spends are verified by using a
spend-tree where spends are scanned against spent outputs instead of
unspent outputs.

This allows for much better concurrency, as not only blocks, but also
individual inputs can be verified fully in parallel.

I explain the approach at https://bitcrust.org, source code is available
at https://github.com/tomasvdw/bitcrust

I am sharing this not only to ask for your feedback, but also to call
for a clear separation of protocol and implementations: As this
solution, reversing the costs of outputs and inputs, seems to have
excellent performance characteristics (as shown in the test results),
updates to the protocol addressing the UTXO growth, might not be worth
considering *protocol improvements* and it might be best to address
these concerns as implementation details.

Kind regards,
Tomas van der Wansem
tomas@bitcrust.org
Bitcrust