<p>Yes, 0.9.5 is consensus compatible with modern Bitcoin, though it will be considerably slower than modern versions, and probably shouldn't be used for anything that's transacting real money.</p>

CC BY-SA 4.0
2021-11-09T19:09:07.627Z
Thank you! That's encouraging.
seamux
CC BY-SA 4.0
2021-11-09T19:11:44.797Z
Just being compatible isn't sufficient to make it synchronize. The block download logic was completely overhauled in 0.10, as it had became barely possible to synchronize even then using the logic that was in 0.9 and earlier versions. You're probably better off synchronizing with maybe 0.12 (last pre-segwit version), exporting the blockchain using the linearize script, and then importing the result in a new 0.9 install.
Pieter Wuille
CC BY-SA 4.0
2021-11-09T19:34:13.600Z
@PieterWuille thank you, that's a great idea.
seamux
CC BY-SA 4.0
2022-02-18T17:50:48.620Z
@PieterWuille by the way it worked
seamux
CC BY-SA 4.0
2021-11-09T18:44:53.037Z
2021-11-09T18:44:53.037Z
Claris
<p>Solo Linux GPU bitcoin miner here (doing it for fun not profit so please, no 'what's the point' answers).  Working mining software for this purpose is far and few in between, but I have been able to get it to work with recent versions of Bitcoin Core with <code>nsgminer</code> to achieve a modest ~2.5 Mhz/s hashrate. <code>nsgminer</code> uses OpenCL, and the word is that CUDA offers much better performance on Nvidia hardware, and I'm curious what kind of hashrate I can get. However, the only miner that could potentially work, would compile with recent versions of CUDA, and available for Linux is <code>klaust/ccminer</code>, which does not support <code>getblocktemplate</code>, while Bitcoin Core got rid of <code>getwork</code> since v0.10.x. So I'm building a new node with v0.9.5, which doesn't work with the blockchain fully built with a much later version. The sync rate slows down significantly aroundd 60% as it starts to struggle to find compatible peers, and now it is almost 80% but seems to inch toward it asymptotically (though I've only been at it for about a day). So my questions is, can v0.9.5 still fully sync? If not, I'd rather not to waste my bandwidth on getting terabytes of unusable packets and just kill it now.</p>

<bitcoin-core><gpu-mining><getwork><getblocktemplate>
Can Bitcoin Core 0.9.5 still fully sync?
seamux
# Can Bitcoin Core 0.9.5 still fully sync?

(Asked by: username_0 on 2021-11-09)

Solo Linux GPU bitcoin miner here (doing it for fun not profit so please, no 'what's the point' answers). Working mining software for this purpose is far and few in between, but I have been able to get it to work with recent versions of Bitcoin Core with `nsgminer` to achieve a modest ~2.5 Mhz/s hashrate. `nsgminer` uses OpenCL, and the word is that CUDA offers much better performance on Nvidia hardware, and I'm curious what kind of hashrate I can get. However, the only miner that could potentially work, would compile with recent versions of CUDA, and available for Linux is `klaust/ccminer`, which does not support `getblocktemplate`, while Bitcoin Core got rid of `getwork` since v0.10.x. So I'm building a new node with v0.9.5, which doesn't work with the blockchain fully built with a much later version. The sync rate slows down significantly aroundd 60% as it starts to struggle to find compatible peers, and now it is almost 80% but seems to inch toward it asymptotically (though I've only been at it for about a day). So my questions is, can v0.9.5 still fully sync? If not, I'd rather not to waste my bandwidth on getting terabytes of unusable packets and just kill it now.

**Tags:** bitcoin-core, gpu-mining, getwork, getblocktemplate


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## 1 answers

### Answer by username_1 on 2021-11-09. Score: 2 | Accepted answer

Yes, 0.9.5 is consensus compatible with modern Bitcoin, though it will be considerably slower than modern versions, and probably shouldn't be used for anything that's transacting real money.

> **Comments:**
> **username_0**: Thank you! That's encouraging.  
> **username_2**: Just being compatible isn't sufficient to make it synchronize. The block download logic was completely overhauled in 0.10, as it had became barely possible to synchronize even then using the logic that was in 0.9 and earlier versions. You're probably better off synchronizing with maybe 0.12 (last pre-segwit version), exporting the blockchain using the linearize script, and then importing the result in a new 0.9 install.  
> **username_0**: @username_2 thank you, that's a great idea.  
> **username_0**: @username_2 by the way it worked  

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