<p>Regarding to the second transaction: It seems that it's a replacement for another transaction: <a href="https://blockchair.com/bitcoin/transaction/3791f433180a6807695da26e1c0b7f7328a15cbe727ad4ce7c7acbc18b77c5a0" rel="nofollow noreferrer">https://blockchair.com/bitcoin/transaction/3791f433180a6807695da26e1c0b7f7328a15cbe727ad4ce7c7acbc18b77c5a0</a>
but it does not allows replacement by bip 125.</p>
<p>As I'm stopping my development node when needed, it seems that this transaction was not in my node before receiving the second one (fa0dee70658fd00d6d205f673e79e3481cdba57100db576f2a7a308591a1c5e0). So it was accepted. The other node I have (pi4) rejects that transaction because its online all the time, and had tx 3791f433180a6807695da26e1c0b7f7328a15cbe727ad4ce7c7acbc18b77c5a0 before.</p>
<p>In brief: Some people/program was sending a replacement for a transaction which does not allow it and my node took it as the original.</p>
<p>Thanks a lot @Murch</p>

CC BY-SA 4.0
2020-11-03T18:25:32.647Z
Right, the original transaction had set all its nSequence numbers to final, so it was not marked for replacement. Therefore the replacement got ignored per the first-seen-safe rule. To read more see https://bitcoin.stackexchange.com/a/49518/5406
Murch
CC BY-SA 4.0
2020-11-07T09:11:42.623Z
For anyone wondering how to seach for transaction outputs in the mempool: blockchair.com has a beta API which allows some queries by value or address. https://blockchair.com/api/docs#link_400
dev7ba
CC BY-SA 4.0
2020-11-03T14:51:14.347Z
2020-11-03T14:51:14.347Z
dev7ba
<p>I've checked my node, and it has no evidence of transaction <code>c3f92fe9ec20218a8c3d38b4852c9a88779d3128abdd43ac8c249207d8d3b530</code>.</p>
<p>Additionally, I checked a couple of block explorer websites, and none of them show any result for this transaction.</p>
<p>So it seems that this transaction was either not relayed through the wider network, or it was dropped by network nodes for some reason (network fees have been very high, some mempools might be hitting their memory limits). Without additional information, it is not possible to know.</p>
<p>Generally, we wouldn't expect all miners to ignore a high-fee-rate transaction, so there must be some other issue at play.</p>

CC BY-SA 4.0
2020-10-30T19:03:11.237Z
2020-10-30T19:03:11.237Z
chytrik
<p>I'm looking into the second tx posted by the asker: fa0dee70658fd00d6d205f673e79e3481cdba57100db576f2a7a308591a1c5e0</p>
<p>It doesn't appear on any explorers. I noticed that all inputs were listed as being <code>vout: 0</code>, e.g. the input list states</p>
<pre><code>{
  &quot;addressIds&quot;: [
    &quot;123h581GZtFAucMPpa3hFBCedEifaka5g9&quot;
  ],
  &quot;amount&quot;: 76559401,
  &quot;txId&quot;: &quot;f9d4f7cc3cae21da8ed864654db405dcbc90a43e811ebafa999aa83c1ec323c9&quot;,
  &quot;coinbase&quot;: null,
  &quot;voutIndex&quot;: 0
},
</code></pre>
<p>for one of the inputs.</p>
<p>However, the unspent was actually the sixth output (<code>vout: 5</code>) when it was created:</p>
<p><a href="https://i.sstatic.net/wwIuk.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/wwIuk.png" alt="enter image description here" /></a></p>
<p>When I put the txhex into <a href="https://blockstream.info/testnet/tx/push" rel="nofollow noreferrer">https://blockstream.info/testnet/tx/push</a>, it fails with <code>sendrawtransaction RPC error: {&quot;code&quot;:-25,&quot;message&quot;:&quot;bad-txns-inputs-missingorspent&quot;}</code>.</p>
<p><a href="https://i.sstatic.net/z5VUU.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/z5VUU.png" alt="enter image description here" /></a>.</p>
<p>The transaction is invalid due to incorrectly specifying the output list position of the UTXO used in the inputs.</p>

CC BY-SA 4.0
2020-11-03T13:18:28.013Z
I'm missing something... then why that transaction is in my mempool? I thought that bitcoin nodes discards incorrect transactions. I have not generated it... I'm puzzled.
dev7ba
CC BY-SA 4.0
2020-11-03T13:25:24.430Z
What node software are you using?
Murch
CC BY-SA 4.0
2020-11-03T13:26:35.887Z
By the way there is a mistake in the json I've sent you. I'm sorry. It was taken from my program instead from bitcoin-rpc. It seems that not all vouts index are 0. but my program are not taking them correctly (I bet I have fogotten a setter somewhere) . anyway something is wrong because the hex value I've sent you is correct.
dev7ba
CC BY-SA 4.0
2020-11-03T13:27:19.350Z
I'm using bitcoin core 0.20.1 on ubuntu
dev7ba
CC BY-SA 4.0
2020-11-03T13:34:33.717Z
I'm getting nervous. F**k me if I've discovered a consensus bug. O_o
dev7ba
CC BY-SA 4.0
2020-11-03T14:11:11.483Z
I have two nodes: one in a raspberry pi and other in my pc. I use Raspberry pi for having the best mempool I can (always online). The other pc is used for development and it's shutdown when needed. When I need a "good" mempool in my pc I use a tool to query all tx in a mempool and send them to the other node. See https://bitcoin.stackexchange.com/questions/63675/synchronize-mempool-between-3-nodes The node that has accepted that tx is the development one. not the pi4. both are 0.20.1 versions. Now I'm sending that transaction from the pc to the pi4. but I get an error code
dev7ba
CC BY-SA 4.0
2020-11-03T14:19:52.360Z
My mistake, you are correct, the vouts in the txhex are correct.
Murch
CC BY-SA 4.0
2020-11-03T14:20:11.693Z
I found this though: https://blockchair.com/bitcoin/transaction/3791f433180a6807695da26e1c0b7f7328a15cbe727ad4ce7c7acbc18b77c5a0
Murch
CC BY-SA 4.0
2020-11-03T14:21:21.180Z
Let us [continue this discussion in chat](https://chat.stackexchange.com/rooms/115795/discussion-between-murch-and-jramos).
Murch
CC BY-SA 4.0
2020-11-03T12:57:24.307Z
2020-11-03T12:57:24.307Z
Murch
<p>I'm working on a project to visualize the mempool and (also) check if a transaction is being ignored by miners.</p>
<p>I have my own mining queue, to compare &quot;my first block&quot; with the block that has been mined. Comparing that block with mine I can take many statistics about weather a miner is choosing the best txs and/or is behaving correctly.</p>
<p>Project is currently in development and I have the backend more or less complete. Front-End is incomplete. So sorry if I can give you a link to it.</p>
<p>Today I've found that tx c3f92fe9ec20218a8c3d38b4852c9a88779d3128abdd43ac8c249207d8d3b530 has been ignored 86 times until now. And currently It's the first transaction that <strong>should</strong> be mined with 786 sat/VByte.</p>
<p>My bitcoin node shows that this transaction entered my mempool 20 hours ago. It's a short transaction with only 764 weight units, one input, one output, 0.24 bitcoins. Nothing special?</p>
<p>Also, my bitcoin node is using the tor network.</p>
<p>The transaction does not appear in known blockchain explorers so it seems that it has not been relayed properly. The transaction has bip125 enabled, so it could be that the person or entity broadcasting that transaction had increased many times the transaction fee.</p>
<p>So I'm wondering what is happening with this transaction. Anybody out there has any idea?</p>
<p>Maybe bitcoin nodes in tor network has poor conectivity with miners?</p>
<p>FYI: These are the blocks who has ignored the transaction up to date:</p>
<pre><code>height: 654568,
totalTxNumMined: 2762,
postitionInQueue: 5
},
{
height: 654569,
totalTxNumMined: 2746,
postitionInQueue: 4
},
{
height: 654570,
totalTxNumMined: 2177,
postitionInQueue: 1
},
{
height: 654571,
totalTxNumMined: 3044,
postitionInQueue: 2
},
{
height: 654572,
totalTxNumMined: 2824,
postitionInQueue: 0
},
{
height: 654574,
totalTxNumMined: 0,
postitionInQueue: 1
},
{
height: 654575,
totalTxNumMined: 2706,
postitionInQueue: 3
},
{
height: 654576,
totalTxNumMined: 2515,
postitionInQueue: 0
},
{
height: 654578,
totalTxNumMined: 3141,
postitionInQueue: 3
},
{
height: 654579,
totalTxNumMined: 3040,
postitionInQueue: 6
},
{
height: 654580,
totalTxNumMined: 2501,
postitionInQueue: 0
},
{
height: 654581,
totalTxNumMined: 2399,
postitionInQueue: 1
},
{
height: 654582,
totalTxNumMined: 2889,
postitionInQueue: 1
},
{
height: 654583,
totalTxNumMined: 2098,
postitionInQueue: 1
},
{
height: 654584,
totalTxNumMined: 2973,
postitionInQueue: 5
},
{
height: 654585,
totalTxNumMined: 2135,
postitionInQueue: 4
},
{
height: 654586,
totalTxNumMined: 2451,
postitionInQueue: 6
},
{
height: 654587,
totalTxNumMined: 2312,
postitionInQueue: 8
},
{
height: 654588,
totalTxNumMined: 2614,
postitionInQueue: 5
},
{
height: 654589,
totalTxNumMined: 2946,
postitionInQueue: 2
},
{
height: 654590,
totalTxNumMined: 3170,
postitionInQueue: 0
},
{
height: 654591,
totalTxNumMined: 2624,
postitionInQueue: 7
},
{
height: 654592,
totalTxNumMined: 2638,
postitionInQueue: 4
},
{
height: 654593,
totalTxNumMined: 2988,
postitionInQueue: 0
},
{
height: 654594,
totalTxNumMined: 2781,
postitionInQueue: 11
},
{
height: 654595,
totalTxNumMined: 2486,
postitionInQueue: 3
},
{
height: 654596,
totalTxNumMined: 2423,
postitionInQueue: 0
},
{
height: 654597,
totalTxNumMined: 2526,
postitionInQueue: 0
},
{
height: 654598,
totalTxNumMined: 2973,
postitionInQueue: 1
},
{
height: 654599,
totalTxNumMined: 2866,
postitionInQueue: 0
},
{
height: 654600,
totalTxNumMined: 2910,
postitionInQueue: 10
},
{
height: 654601,
totalTxNumMined: 1814,
postitionInQueue: 0
},
{
height: 654602,
totalTxNumMined: 2642,
postitionInQueue: 0
},
{
height: 654603,
totalTxNumMined: 2572,
postitionInQueue: 0
},
{
height: 654604,
totalTxNumMined: 2068,
postitionInQueue: 0
},
{
height: 654605,
totalTxNumMined: 2300,
postitionInQueue: 1
},
{
height: 654606,
totalTxNumMined: 1911,
postitionInQueue: 3
},
{
height: 654607,
totalTxNumMined: 2503,
postitionInQueue: 0
},
{
height: 654608,
totalTxNumMined: 2060,
postitionInQueue: 1
},
{
height: 654609,
totalTxNumMined: 1666,
postitionInQueue: 5
},
{
height: 654610,
totalTxNumMined: 2241,
postitionInQueue: 1
},
{
height: 654611,
totalTxNumMined: 1947,
postitionInQueue: 0
},
{
height: 654612,
totalTxNumMined: 1496,
postitionInQueue: 0
},
{
height: 654613,
totalTxNumMined: 2140,
postitionInQueue: 4
},
{
height: 654614,
totalTxNumMined: 2460,
postitionInQueue: 0
},
{
height: 654615,
totalTxNumMined: 1338,
postitionInQueue: 2
},
{
height: 654616,
totalTxNumMined: 2320,
postitionInQueue: 0
},
{
height: 654617,
totalTxNumMined: 2394,
postitionInQueue: 2
},
{
height: 654618,
totalTxNumMined: 2630,
postitionInQueue: 1
},
{
height: 654619,
totalTxNumMined: 2858,
postitionInQueue: 0
},
{
height: 654620,
totalTxNumMined: 2097,
postitionInQueue: 0
},
{
height: 654621,
totalTxNumMined: 2856,
postitionInQueue: 5
},
{
height: 654622,
totalTxNumMined: 2379,
postitionInQueue: 1
},
{
height: 654623,
totalTxNumMined: 2585,
postitionInQueue: 5
},
{
height: 654624,
totalTxNumMined: 2434,
postitionInQueue: 2
},
{
height: 654625,
totalTxNumMined: 2032,
postitionInQueue: 6
},
{
height: 654626,
totalTxNumMined: 2667,
postitionInQueue: 4
},
{
height: 654627,
totalTxNumMined: 2521,
postitionInQueue: 1
},
{
height: 654628,
totalTxNumMined: 2662,
postitionInQueue: 1
},
{
height: 654629,
totalTxNumMined: 2313,
postitionInQueue: 1
},
{
height: 654630,
totalTxNumMined: 1995,
postitionInQueue: 0
},
{
height: 654631,
totalTxNumMined: 2330,
postitionInQueue: 0
},
{
height: 654632,
totalTxNumMined: 2588,
postitionInQueue: 0
},
{
height: 654633,
totalTxNumMined: 2775,
postitionInQueue: 3
},
{
height: 654634,
totalTxNumMined: 2604,
postitionInQueue: 0
},
{
height: 654635,
totalTxNumMined: 2135,
postitionInQueue: 0
},
{
height: 654636,
totalTxNumMined: 2540,
postitionInQueue: 2
},
{
height: 654637,
totalTxNumMined: 2244,
postitionInQueue: 0
},
{
height: 654638,
totalTxNumMined: 1231,
postitionInQueue: 1
},
{
height: 654639,
totalTxNumMined: 2367,
postitionInQueue: 1
},
{
height: 654640,
totalTxNumMined: 2370,
postitionInQueue: 0
},
{
height: 654641,
totalTxNumMined: 2935,
postitionInQueue: 4
},
{
height: 654642,
totalTxNumMined: 2453,
postitionInQueue: 1
},
{
height: 654643,
totalTxNumMined: 2414,
postitionInQueue: 0
},
{
height: 654644,
totalTxNumMined: 3102,
postitionInQueue: 6
},
{
height: 654645,
totalTxNumMined: 3211,
postitionInQueue: 5
},
{
height: 654646,
totalTxNumMined: 2561,
postitionInQueue: 0
},
{
height: 654648,
totalTxNumMined: 1931,
postitionInQueue: 10
},
{
height: 654649,
totalTxNumMined: 2578,
postitionInQueue: 2
},
{
height: 654650,
totalTxNumMined: 2588,
postitionInQueue: 0
},
{
height: 654651,
totalTxNumMined: 3038,
postitionInQueue: 7
},
{
height: 654652,
totalTxNumMined: 1305,
postitionInQueue: 0
},
{
height: 654653,
totalTxNumMined: 2260,
postitionInQueue: 3
},
{
height: 654654,
totalTxNumMined: 2627,
postitionInQueue: 1
},
{
height: 654655,
totalTxNumMined: 1980,
postitionInQueue: 2
},
{
height: 654656,
totalTxNumMined: 2645,
postitionInQueue: 0
},
{
height: 654658,
totalTxNumMined: 2861,
postitionInQueue: 5
}```
</code></pre>

CC BY-SA 4.0
2020-10-30T19:06:18.880Z
Is it possible that the transaction depending on unconfirmed inputs? It would help if you provided the full transaction, especially its input set.
Murch
CC BY-SA 4.0
2020-10-31T20:03:43.683Z
No, the transaction was not dependant on any other, (my project even draw a graph of txs dependencies). but sadly I've had to delete mempool.dat of my mempool node since my algorithm was not performing fine under the big mempool of last days, the cpu was 100%, and my computer was stuck. Anyway I'll be monitoring the mempool next days. If I found any other Txs. I'll let you know. By the way I'll read your Master Thesis next days. ;-) Thanks.
dev7ba
CC BY-SA 4.0
2020-10-31T20:56:24.047Z
I agree with Chytrik, my first bunch would also expect some other issue at play. I'll be curious to hear about it when you find another.
Murch
CC BY-SA 4.0
2020-11-03T12:18:02.147Z
fa0dee70658fd00d6d205f673e79e3481cdba57100db576f2a7a308591a1c5e0 does not appear in https://mempool.observer/ nor https://blockstream.info or https://mempool.space Pays 64 sat/VByte which is now enough  to be mined. Has been ignored 14 times from block 655212 to 655227 by miners: huobi, bitdeer, 1thash&58coin, poolin, antpool, f2pool, btc.com and binance.
dev7ba
CC BY-SA 4.0
2020-11-03T12:25:06.690Z
Depends on txs: b6bc98c8d29893f2a6e04fa3bd84f60958293739dbec0af8670c446247c3c923, 23dff917408de07b05762ceb3ebe90b07889e5da6ed74d8f4d607d3bae20705e, 414ba5ca29d582452d101a26c944b2a8ffa3e0c6407215ca0ef08c9d5dd3e0d8, f9d4f7cc3cae21da8ed864654db405dcbc90a43e811ebafa999aa83c1ec323c9, 0020bc825433a7f085afcd3288f6eb7868b806bb9efa6461ad1e7e1f2b733138 each one been confirmed 30000 blocks ago...
dev7ba
CC BY-SA 4.0
2020-11-03T12:30:10.147Z
I cannot paste the hexadecimal representation here because it's too long. weight: 3116. Do you need more information?
dev7ba
CC BY-SA 4.0
2020-11-03T12:34:50.760Z
I don't see the transaction on blockexplorers. I think it might be non-standard. Could you post the tx in a gist on github for example?
Murch
CC BY-SA 4.0
2020-11-03T12:57:47.853Z
Great, thanks. The tx is invalid. See my answer
Murch
<mining-pools><mempool>
Transaction being ignored by miners, I mean Ignored, Not "not mined because low fees"
dev7ba
# Transaction being ignored by miners, I mean Ignored, Not "not mined because low fees"

(Asked by: username_0 on 2020-10-29)

I'm working on a project to visualize the mempool and (also) check if a transaction is being ignored by miners.

I have my own mining queue, to compare "my first block" with the block that has been mined. Comparing that block with mine I can take many statistics about weather a miner is choosing the best txs and/or is behaving correctly.

Project is currently in development and I have the backend more or less complete. Front-End is incomplete. So sorry if I can give you a link to it.

Today I've found that tx c3f92fe9ec20218a8c3d38b4852c9a88779d3128abdd43ac8c249207d8d3b530 has been ignored 86 times until now. And currently It's the first transaction that **should** be mined with 786 sat/VByte.

My bitcoin node shows that this transaction entered my mempool 20 hours ago. It's a short transaction with only 764 weight units, one input, one output, 0.24 bitcoins. Nothing special?

Also, my bitcoin node is using the tor network.

The transaction does not appear in known blockchain explorers so it seems that it has not been relayed properly. The transaction has bip125 enabled, so it could be that the person or entity broadcasting that transaction had increased many times the transaction fee.

So I'm wondering what is happening with this transaction. Anybody out there has any idea?

Maybe bitcoin nodes in tor network has poor conectivity with miners?

FYI: These are the blocks who has ignored the transaction up to date:

```
height: 654568,
totalTxNumMined: 2762,
postitionInQueue: 5
},
{
height: 654569,
totalTxNumMined: 2746,
postitionInQueue: 4
},
{
height: 654570,
totalTxNumMined: 2177,
postitionInQueue: 1
},
{
height: 654571,
totalTxNumMined: 3044,
postitionInQueue: 2
},
{
height: 654572,
totalTxNumMined: 2824,
postitionInQueue: 0
},
{
height: 654574,
totalTxNumMined: 0,
postitionInQueue: 1
},
{
height: 654575,
totalTxNumMined: 2706,
postitionInQueue: 3
},
{
height: 654576,
totalTxNumMined: 2515,
postitionInQueue: 0
},
{
height: 654578,
totalTxNumMined: 3141,
postitionInQueue: 3
},
{
height: 654579,
totalTxNumMined: 3040,
postitionInQueue: 6
},
{
height: 654580,
totalTxNumMined: 2501,
postitionInQueue: 0
},
{
height: 654581,
totalTxNumMined: 2399,
postitionInQueue: 1
},
{
height: 654582,
totalTxNumMined: 2889,
postitionInQueue: 1
},
{
height: 654583,
totalTxNumMined: 2098,
postitionInQueue: 1
},
{
height: 654584,
totalTxNumMined: 2973,
postitionInQueue: 5
},
{
height: 654585,
totalTxNumMined: 2135,
postitionInQueue: 4
},
{
height: 654586,
totalTxNumMined: 2451,
postitionInQueue: 6
},
{
height: 654587,
totalTxNumMined: 2312,
postitionInQueue: 8
},
{
height: 654588,
totalTxNumMined: 2614,
postitionInQueue: 5
},
{
height: 654589,
totalTxNumMined: 2946,
postitionInQueue: 2
},
{
height: 654590,
totalTxNumMined: 3170,
postitionInQueue: 0
},
{
height: 654591,
totalTxNumMined: 2624,
postitionInQueue: 7
},
{
height: 654592,
totalTxNumMined: 2638,
postitionInQueue: 4
},
{
height: 654593,
totalTxNumMined: 2988,
postitionInQueue: 0
},
{
height: 654594,
totalTxNumMined: 2781,
postitionInQueue: 11
},
{
height: 654595,
totalTxNumMined: 2486,
postitionInQueue: 3
},
{
height: 654596,
totalTxNumMined: 2423,
postitionInQueue: 0
},
{
height: 654597,
totalTxNumMined: 2526,
postitionInQueue: 0
},
{
height: 654598,
totalTxNumMined: 2973,
postitionInQueue: 1
},
{
height: 654599,
totalTxNumMined: 2866,
postitionInQueue: 0
},
{
height: 654600,
totalTxNumMined: 2910,
postitionInQueue: 10
},
{
height: 654601,
totalTxNumMined: 1814,
postitionInQueue: 0
},
{
height: 654602,
totalTxNumMined: 2642,
postitionInQueue: 0
},
{
height: 654603,
totalTxNumMined: 2572,
postitionInQueue: 0
},
{
height: 654604,
totalTxNumMined: 2068,
postitionInQueue: 0
},
{
height: 654605,
totalTxNumMined: 2300,
postitionInQueue: 1
},
{
height: 654606,
totalTxNumMined: 1911,
postitionInQueue: 3
},
{
height: 654607,
totalTxNumMined: 2503,
postitionInQueue: 0
},
{
height: 654608,
totalTxNumMined: 2060,
postitionInQueue: 1
},
{
height: 654609,
totalTxNumMined: 1666,
postitionInQueue: 5
},
{
height: 654610,
totalTxNumMined: 2241,
postitionInQueue: 1
},
{
height: 654611,
totalTxNumMined: 1947,
postitionInQueue: 0
},
{
height: 654612,
totalTxNumMined: 1496,
postitionInQueue: 0
},
{
height: 654613,
totalTxNumMined: 2140,
postitionInQueue: 4
},
{
height: 654614,
totalTxNumMined: 2460,
postitionInQueue: 0
},
{
height: 654615,
totalTxNumMined: 1338,
postitionInQueue: 2
},
{
height: 654616,
totalTxNumMined: 2320,
postitionInQueue: 0
},
{
height: 654617,
totalTxNumMined: 2394,
postitionInQueue: 2
},
{
height: 654618,
totalTxNumMined: 2630,
postitionInQueue: 1
},
{
height: 654619,
totalTxNumMined: 2858,
postitionInQueue: 0
},
{
height: 654620,
totalTxNumMined: 2097,
postitionInQueue: 0
},
{
height: 654621,
totalTxNumMined: 2856,
postitionInQueue: 5
},
{
height: 654622,
totalTxNumMined: 2379,
postitionInQueue: 1
},
{
height: 654623,
totalTxNumMined: 2585,
postitionInQueue: 5
},
{
height: 654624,
totalTxNumMined: 2434,
postitionInQueue: 2
},
{
height: 654625,
totalTxNumMined: 2032,
postitionInQueue: 6
},
{
height: 654626,
totalTxNumMined: 2667,
postitionInQueue: 4
},
{
height: 654627,
totalTxNumMined: 2521,
postitionInQueue: 1
},
{
height: 654628,
totalTxNumMined: 2662,
postitionInQueue: 1
},
{
height: 654629,
totalTxNumMined: 2313,
postitionInQueue: 1
},
{
height: 654630,
totalTxNumMined: 1995,
postitionInQueue: 0
},
{
height: 654631,
totalTxNumMined: 2330,
postitionInQueue: 0
},
{
height: 654632,
totalTxNumMined: 2588,
postitionInQueue: 0
},
{
height: 654633,
totalTxNumMined: 2775,
postitionInQueue: 3
},
{
height: 654634,
totalTxNumMined: 2604,
postitionInQueue: 0
},
{
height: 654635,
totalTxNumMined: 2135,
postitionInQueue: 0
},
{
height: 654636,
totalTxNumMined: 2540,
postitionInQueue: 2
},
{
height: 654637,
totalTxNumMined: 2244,
postitionInQueue: 0
},
{
height: 654638,
totalTxNumMined: 1231,
postitionInQueue: 1
},
{
height: 654639,
totalTxNumMined: 2367,
postitionInQueue: 1
},
{
height: 654640,
totalTxNumMined: 2370,
postitionInQueue: 0
},
{
height: 654641,
totalTxNumMined: 2935,
postitionInQueue: 4
},
{
height: 654642,
totalTxNumMined: 2453,
postitionInQueue: 1
},
{
height: 654643,
totalTxNumMined: 2414,
postitionInQueue: 0
},
{
height: 654644,
totalTxNumMined: 3102,
postitionInQueue: 6
},
{
height: 654645,
totalTxNumMined: 3211,
postitionInQueue: 5
},
{
height: 654646,
totalTxNumMined: 2561,
postitionInQueue: 0
},
{
height: 654648,
totalTxNumMined: 1931,
postitionInQueue: 10
},
{
height: 654649,
totalTxNumMined: 2578,
postitionInQueue: 2
},
{
height: 654650,
totalTxNumMined: 2588,
postitionInQueue: 0
},
{
height: 654651,
totalTxNumMined: 3038,
postitionInQueue: 7
},
{
height: 654652,
totalTxNumMined: 1305,
postitionInQueue: 0
},
{
height: 654653,
totalTxNumMined: 2260,
postitionInQueue: 3
},
{
height: 654654,
totalTxNumMined: 2627,
postitionInQueue: 1
},
{
height: 654655,
totalTxNumMined: 1980,
postitionInQueue: 2
},
{
height: 654656,
totalTxNumMined: 2645,
postitionInQueue: 0
},
{
height: 654658,
totalTxNumMined: 2861,
postitionInQueue: 5
}```

```

**Tags:** mining-pools, mempool

> **Comments:**
> **username_1**: Is it possible that the transaction depending on unconfirmed inputs? It would help if you provided the full transaction, especially its input set.  
> **username_0**: No, the transaction was not dependant on any other, (my project even draw a graph of txs dependencies). but sadly I've had to delete mempool.dat of my mempool node since my algorithm was not performing fine under the big mempool of last days, the cpu was 100%, and my computer was stuck. Anyway I'll be monitoring the mempool next days. If I found any other Txs. I'll let you know. By the way I'll read your Master Thesis next days. ;-) Thanks.  
> **username_1**: I agree with username_2, my first bunch would also expect some other issue at play. I'll be curious to hear about it when you find another.  
> **username_0**: fa0dee70658fd00d6d205f673e79e3481cdba57100db576f2a7a308591a1c5e0 does not appear in https://mempool.observer/ nor https://blockstream.info or https://mempool.space Pays 64 sat/VByte which is now enough  to be mined. Has been ignored 14 times from block 655212 to 655227 by miners: huobi, bitdeer, 1thash&58coin, poolin, antpool, f2pool, btc.com and binance.  
> **username_0**: Depends on txs: b6bc98c8d29893f2a6e04fa3bd84f60958293739dbec0af8670c446247c3c923, 23dff917408de07b05762ceb3ebe90b07889e5da6ed74d8f4d607d3bae20705e, 414ba5ca29d582452d101a26c944b2a8ffa3e0c6407215ca0ef08c9d5dd3e0d8, f9d4f7cc3cae21da8ed864654db405dcbc90a43e811ebafa999aa83c1ec323c9, 0020bc825433a7f085afcd3288f6eb7868b806bb9efa6461ad1e7e1f2b733138 each one been confirmed 30000 blocks ago...  
> **username_0**: I cannot paste the hexadecimal representation here because it's too long. weight: 3116. Do you need more information?  
> **username_1**: I don't see the transaction on blockexplorers. I think it might be non-standard. Could you post the tx in a gist on github for example?  
> **username_1**: Great, thanks. The tx is invalid. See my answer  

---

## 3 answers

### Answer by username_0 on 2020-11-03. Score: 2 | Accepted answer

Regarding to the second transaction: It seems that it's a replacement for another transaction: <https://blockchair.com/bitcoin/transaction/3791f433180a6807695da26e1c0b7f7328a15cbe727ad4ce7c7acbc18b77c5a0>
but it does not allows replacement by bip 125.

As I'm stopping my development node when needed, it seems that this transaction was not in my node before receiving the second one (fa0dee70658fd00d6d205f673e79e3481cdba57100db576f2a7a308591a1c5e0). So it was accepted. The other node I have (pi4) rejects that transaction because its online all the time, and had tx 3791f433180a6807695da26e1c0b7f7328a15cbe727ad4ce7c7acbc18b77c5a0 before.

In brief: Some people/program was sending a replacement for a transaction which does not allow it and my node took it as the original.

Thanks a lot @username_1

> **Comments:**
> **username_1**: Right, the original transaction had set all its nSequence numbers to final, so it was not marked for replacement. Therefore the replacement got ignored per the first-seen-safe rule. To read more see https://bitcoin.stackexchange.com/a/49518/5406  
> **username_0**: For anyone wondering how to seach for transaction outputs in the mempool: blockchair.com has a beta API which allows some queries by value or address. https://blockchair.com/api/docs#link_400  

---

### Answer by username_2 on 2020-10-30. Score: 1

I've checked my node, and it has no evidence of transaction `c3f92fe9ec20218a8c3d38b4852c9a88779d3128abdd43ac8c249207d8d3b530`.

Additionally, I checked a couple of block explorer websites, and none of them show any result for this transaction.

So it seems that this transaction was either not relayed through the wider network, or it was dropped by network nodes for some reason (network fees have been very high, some mempools might be hitting their memory limits). Without additional information, it is not possible to know.

Generally, we wouldn't expect all miners to ignore a high-fee-rate transaction, so there must be some other issue at play.


---

### Answer by username_1 on 2020-11-03. Score: 1

I'm looking into the second tx posted by the asker: fa0dee70658fd00d6d205f673e79e3481cdba57100db576f2a7a308591a1c5e0

It doesn't appear on any explorers. I noticed that all inputs were listed as being `vout: 0`, e.g. the input list states

```
{
  "addressIds": [
    "123h581GZtFAucMPpa3hFBCedEifaka5g9"
  ],
  "amount": 76559401,
  "txId": "f9d4f7cc3cae21da8ed864654db405dcbc90a43e811ebafa999aa83c1ec323c9",
  "coinbase": null,
  "voutIndex": 0
},

```

for one of the inputs.

However, the unspent was actually the sixth output (`vout: 5`) when it was created:

[![enter image description here](https://i.sstatic.net/wwIuk.png)](https://i.sstatic.net/wwIuk.png)

When I put the txhex into <https://blockstream.info/testnet/tx/push>, it fails with `sendrawtransaction RPC error: {"code":-25,"message":"bad-txns-inputs-missingorspent"}`.

[![enter image description here](https://i.sstatic.net/z5VUU.png)](https://i.sstatic.net/z5VUU.png).

The transaction is invalid due to incorrectly specifying the output list position of the UTXO used in the inputs.

> **Comments:**
> **username_0**: I'm missing something... then why that transaction is in my mempool? I thought that bitcoin nodes discards incorrect transactions. I have not generated it... I'm puzzled.  
> **username_1**: What node software are you using?  
> **username_0**: By the way there is a mistake in the json I've sent you. I'm sorry. It was taken from my program instead from bitcoin-rpc. It seems that not all vouts index are 0. but my program are not taking them correctly (I bet I have fogotten a setter somewhere) . anyway something is wrong because the hex value I've sent you is correct.  
> **username_0**: I'm using bitcoin core 0.20.1 on ubuntu  
> **username_0**: I'm getting nervous. F**k me if I've discovered a consensus bug. O_o  
> **username_0**: I have two nodes: one in a raspberry pi and other in my pc. I use Raspberry pi for having the best mempool I can (always online). The other pc is used for development and it's shutdown when needed. When I need a "good" mempool in my pc I use a tool to query all tx in a mempool and send them to the other node. See https://bitcoin.stackexchange.com/questions/63675/synchronize-mempool-between-3-nodes The node that has accepted that tx is the development one. not the pi4. both are 0.20.1 versions. Now I'm sending that transaction from the pc to the pi4. but I get an error code  
> **username_1**: My mistake, you are correct, the vouts in the txhex are correct.  
> **username_1**: I found this though: https://blockchair.com/bitcoin/transaction/3791f433180a6807695da26e1c0b7f7328a15cbe727ad4ce7c7acbc18b77c5a0  
> **username_1**: Let us [continue this discussion in chat](https://chat.stackexchange.com/rooms/115795/discussion-between-username_1-and-jramos).  

---

