<p>It seems to me that you should be able to make the <code>importmempool</code> call, but given that most transactions would probably be spending fairly young UTXOs, I would expect that almost all transactions would end up in the orphanage rather than the mempool due to spending unknown UTXOs.</p>
<p>I have not tried, it seems also possible that <code>importmempool</code> would just be outright disabled during IBD.</p>

CC BY-SA 4.0
2024-09-11T17:04:57.783Z
2024-09-11T17:04:57.783Z
Murch
<p>Sometimes you might want to experiment with the mainnet mempool but unfortunately  your node has to finish IBD up to the latest chaintip for you to fill up your mempool.</p>

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2023-09-01T14:21:32.280Z
Looks like the answer is in the question?
Antoine Poinsot
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2023-09-01T14:23:01.883Z
I’m not sure. I think that nodes will not ask for unconfirmed transactions from peers until they’ve caught up to the chaintip, but they might be able to use `importmempool`. I think that’s what the question is about.
Murch
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2023-09-01T14:45:46.243Z
Yes using the `importmempool` rpc
Abubakar Sadiq Ismail
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2023-09-01T15:14:59.467Z
Do you mean can a node which has not finished IBD import a *current* mempool with `importmempool` (as in a mempool from a point in time far in the past compared to what the node is synchronized to)? If so, no, because all the mempool's transactions will be invalid (the importmempool RPC will succeed, but it won't actually import anything).
Pieter Wuille
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2023-09-01T15:50:09.053Z
Ah, that’s a good point. Only transactions for which your node already knows about the UTXOs that the inputs are spending and the timelock has been reached will be valid.
Murch
<synchronization><mempool>
Can nodes that did not finish IBD import mempool using the importmempool rpc?
Abubakar Sadiq Ismail
# Can nodes that did not finish IBD import mempool using the importmempool rpc?

(Asked by: username_0 on 2023-09-01)

Sometimes you might want to experiment with the mainnet mempool but unfortunately your node has to finish IBD up to the latest chaintip for you to fill up your mempool.

**Tags:** synchronization, mempool

> **Comments:**
> **username_1**: Looks like the answer is in the question?  
> **username_2**: I’m not sure. I think that nodes will not ask for unconfirmed transactions from peers until they’ve caught up to the chaintip, but they might be able to use `importmempool`. I think that’s what the question is about.  
> **username_0**: Yes using the `importmempool` rpc  
> **username_3**: Do you mean can a node which has not finished IBD import a *current* mempool with `importmempool` (as in a mempool from a point in time far in the past compared to what the node is synchronized to)? If so, no, because all the mempool's transactions will be invalid (the importmempool RPC will succeed, but it won't actually import anything).  
> **username_2**: Ah, that’s a good point. Only transactions for which your node already knows about the UTXOs that the inputs are spending and the timelock has been reached will be valid.  

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## 1 answers

### Answer by username_2 on 2024-09-11. Score: 1 | Accepted answer

It seems to me that you should be able to make the `importmempool` call, but given that most transactions would probably be spending fairly young UTXOs, I would expect that almost all transactions would end up in the orphanage rather than the mempool due to spending unknown UTXOs.

I have not tried, it seems also possible that `importmempool` would just be outright disabled during IBD.


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