Something very peculiar has happened with a transaction and I would like to understand what network conditions can possibly be the cause of this.
I transferred about 150mBTC from my Android wallet to my bitcoin core HD wallet (
v0.13.0) I have done quite a few of these transfers, and typically within at most a few seconds, the transaction is relayed by the network and appears in my bitcoin core mempool. In this case, the transaction still has not been seen by
bitcoin-qt for almost an hour. It is a very ordinary transaction with quite a high fee of 0.1 mBTC (for only 225 bytes).
I initially thought that my Android had failed to broadcast the transaction. However, this assumption can be dismissed as blockchain.info has successfully received it, providing me with a transaction id.
I then thought that
bitcoin-qt possibly did not recognize the transaction was in relation to my HD wallet. However, it seems that the transaction was in fact never received by my node:
$ cat ~/.bitcoin/debug.log | grep <transaction id> # nothing appears
So I am now under the impression that the transaction was successfully broadcast but for some reason was never relayed to my node. In fact, something like 5 new blocks have appeared since the initial broadcast and the transaction still isn't confirmed (which given the level of fees and no apparent network bottleneck seems very unusual). So I am now under the impression that some miners may not have seen the transaction either (after all if this can happen to my node, why not others?)
Incidentally I have tried to re-broadcast the transaction with https://blockchain.info/pushtx and the raw transaction id, but it tells me the transaction already exists.
Does anyone have a plausible explanation of what may trigger this sort of rare event, where a transaction is seemingly successfully broadcast, but not all nodes seem to hear about it (assuming this interpretation is valid)?
Actually looking at https://blockchain.info/unconfirmed-transactions, as I was writing up this question until now, the number has been rising and is now showing about
18k unmatched transactions which seems to point at abnormal network conditions (typically
EDIT: The transaction was eventually confirmed about 10 blocks later. The fact remains that it was seemingly never relayed to my node until its inclusion in a new block.