Topic: Are we stress testing again? - page 14. (Read 33162 times)

Quote from: turvarya on July 16, 2015, 12:17:10 PM

At some point, the network will "forget" you transaction.

Where is this officially documented? Provide a link please. I find it concerning that a transaction sent could be "forgotten" by the network for any reason, that seems like a huge problem.

I don't have a link, I will get back to you with that if I can find it. However, I know this after looking in the source code. Nodes will only relay transactions once when they receive it or when another node asks for it. The sending node will continue to broadcast the transaction while it is unconfirmed. If it stops broadcasting it, over time nodes will begin to not have the transaction in their mempools, either from restarts or other rules that people might set. Once enough nodes have dropped a transaction, a double spend can be attempted and if that double spend is confirmed, then the original will be dropped as a double spend.

malykii

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Quote from: ?? on ??

When you delete a transaction from your wallet, doesn't mean the other nodes will delete it. Right?
Does Replace-By-Fee mean that you can replace the output-address? If so, then this "feature" just seriously breaks Bitcoin.

That is why a transaction is not a real transaction until it has at least one confirmation (is included into a block). Before then, it is just a transaction "candidate"...

Merchants should never ship products before getting at least one confirmation.

In my case of having a merchant use BitPay I was just provided an address to send BTC, and once it reached the requested amount I received a receipt from the merchant saying I was all set. It was a paid service, so my access has already been updated for what I paid for, and I am guessing if the transaction just doesn't go through BitPay will be out of luck.

RoadTrain

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Quote from: Mikestang on July 16, 2015, 12:19:28 PM

Quote from: Mikestang on July 16, 2015, 12:19:28 PM

At some point, the network will "forget" you transaction.

Where is this officially documented? Provide a link please. I find it concerning that a transaction sent could be "forgotten" by the network for any reason, that seems like a huge problem.

It will sit in some nodes' mempools, but won't be relayed. To my knowledge, transactions are relayed only once, when a node get it for the first time. It means that when some nodes are restarted, they won't have this transaction in their mempools anymore.

To counter that, the nodes that are sender/recipient of this transaction will rebroadcast it from time to time until it gets confirmed.

2112

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Where is this officially documented? Provide a link please. I find it concerning that a transaction sent could be "forgotten" by the network for any reason, that seems like a huge problem.

Use the Source, Luke!

It is documented in the source code. The mempool is a really lame implementation of https://en.wikipedia.org/wiki/In-memory_database . There's no mempool synchronization in the protocol, so eventually the non-confirmed transactions will get forgotten as users restart their nodes.

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At some point, the network will "forget" you transaction.

Where is this officially documented? Provide a link please. I find it concerning that a transaction sent could be "forgotten" by the network for any reason, that seems like a huge problem.

turvarya

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Quote from: malykii on July 16, 2015, 11:25:24 AM

Quote from: RoadTrain on July 16, 2015, 10:12:28 AM

I am not sure if this has been said in this thread, and it seems to be a lot of back and forth from the pages I read, so I figured I would just ask.

If I sent a transaction and didn't set the fee high enough, will the transaction eventually roll back? The BTC have left my wallet at this point, and it was for a paid service, so I am wondering if I have to worry about the transaction not going through.

It was through BitPay, so the vendor got their money I am sure, but I didn't know if the transaction itself would revert back because of the backlog.

The BTC has not really left your wallet until the transaction is included in a block (confirmed). It means you can 'override' your transaction, but it depends on your client.

Which client can "override" a transaction aka double spend it?
How do they trick the nodes, that just won't accept a double spend in their mempool?

You can create a double spend with Bitcoin Core using console commands. Also, since some nodes won't relay or accept transactions with low fees, changing the fee get the double spend accepted into some mempools when the original did not. Otherwise, nodes that enabled Replace-By-Fee will allow double spends as long as the fee is greater than the original and nodes that are Bitcoin XT will relay double spends.

Say I don't go the double spend route. Will the low fee transaction be cleared out the of the mempool at some point, or will it just eventually get processed?

At some point, the network will "forget" you transaction. You just need to either delete it from your wallet or not run your client for a few days. It will be as if the transaction never happened.

When you delete a transaction from your wallet, doesn't mean the other nodes will delete it. Right?
Does Replace-By-Fee mean that you can replace the output-address? If so, then this "feature" just seriously breaks Bitcoin.

malykii

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Quote from: malykii on July 16, 2015, 11:25:24 AM

Quote from: RoadTrain on July 16, 2015, 10:12:28 AM

Quote from: malykii on July 16, 2015, 11:25:24 AM

I am not sure if this has been said in this thread, and it seems to be a lot of back and forth from the pages I read, so I figured I would just ask.

If I sent a transaction and didn't set the fee high enough, will the transaction eventually roll back? The BTC have left my wallet at this point, and it was for a paid service, so I am wondering if I have to worry about the transaction not going through.

It was through BitPay, so the vendor got their money I am sure, but I didn't know if the transaction itself would revert back because of the backlog.

The BTC has not really left your wallet until the transaction is included in a block (confirmed). It means you can 'override' your transaction, but it depends on your client.

Which client can "override" a transaction aka double spend it?
How do they trick the nodes, that just won't accept a double spend in their mempool?

You can create a double spend with Bitcoin Core using console commands. Also, since some nodes won't relay or accept transactions with low fees, changing the fee get the double spend accepted into some mempools when the original did not. Otherwise, nodes that enabled Replace-By-Fee will allow double spends as long as the fee is greater than the original and nodes that are Bitcoin XT will relay double spends.

Say I don't go the double spend route. Will the low fee transaction be cleared out the of the mempool at some point, or will it just eventually get processed?

At some point, the network will "forget" you transaction. You just need to either delete it from your wallet or not run your client for a few days. It will be as if the transaction never happened.

Interesting. So it is potentially possible that BitPay never gets that transaction, and I receive what I purchased for free.

achow101

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Just writing some code

Quote from: RoadTrain on July 16, 2015, 10:12:28 AM

I am not sure if this has been said in this thread, and it seems to be a lot of back and forth from the pages I read, so I figured I would just ask.

If I sent a transaction and didn't set the fee high enough, will the transaction eventually roll back? The BTC have left my wallet at this point, and it was for a paid service, so I am wondering if I have to worry about the transaction not going through.

It was through BitPay, so the vendor got their money I am sure, but I didn't know if the transaction itself would revert back because of the backlog.

The BTC has not really left your wallet until the transaction is included in a block (confirmed). It means you can 'override' your transaction, but it depends on your client.

Which client can "override" a transaction aka double spend it?
How do they trick the nodes, that just won't accept a double spend in their mempool?

You can create a double spend with Bitcoin Core using console commands. Also, since some nodes won't relay or accept transactions with low fees, changing the fee get the double spend accepted into some mempools when the original did not. Otherwise, nodes that enabled Replace-By-Fee will allow double spends as long as the fee is greater than the original and nodes that are Bitcoin XT will relay double spends.

Say I don't go the double spend route. Will the low fee transaction be cleared out the of the mempool at some point, or will it just eventually get processed?

At some point, the network will "forget" you transaction. You just need to either delete it from your wallet or not run your client for a few days. It will be as if the transaction never happened.

malykii

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Activity: 43

Merit: 0

Quote from: RoadTrain on July 16, 2015, 10:12:28 AM

I am not sure if this has been said in this thread, and it seems to be a lot of back and forth from the pages I read, so I figured I would just ask.

If I sent a transaction and didn't set the fee high enough, will the transaction eventually roll back? The BTC have left my wallet at this point, and it was for a paid service, so I am wondering if I have to worry about the transaction not going through.

It was through BitPay, so the vendor got their money I am sure, but I didn't know if the transaction itself would revert back because of the backlog.

The BTC has not really left your wallet until the transaction is included in a block (confirmed). It means you can 'override' your transaction, but it depends on your client.

Which client can "override" a transaction aka double spend it?
How do they trick the nodes, that just won't accept a double spend in their mempool?

You can create a double spend with Bitcoin Core using console commands. Also, since some nodes won't relay or accept transactions with low fees, changing the fee get the double spend accepted into some mempools when the original did not. Otherwise, nodes that enabled Replace-By-Fee will allow double spends as long as the fee is greater than the original and nodes that are Bitcoin XT will relay double spends.

Say I don't go the double spend route. Will the low fee transaction be cleared out the of the mempool at some point, or will it just eventually get processed?

achow101

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Activity: 3374

Merit: 6530

Just writing some code

Quote from: RoadTrain on July 16, 2015, 10:12:28 AM

Quote from: RoadTrain on July 16, 2015, 10:12:28 AM

I am not sure if this has been said in this thread, and it seems to be a lot of back and forth from the pages I read, so I figured I would just ask.

If I sent a transaction and didn't set the fee high enough, will the transaction eventually roll back? The BTC have left my wallet at this point, and it was for a paid service, so I am wondering if I have to worry about the transaction not going through.

It was through BitPay, so the vendor got their money I am sure, but I didn't know if the transaction itself would revert back because of the backlog.

The BTC has not really left your wallet until the transaction is included in a block (confirmed). It means you can 'override' your transaction, but it depends on your client.

Which client can "override" a transaction aka double spend it?
How do they trick the nodes, that just won't accept a double spend in their mempool?

You can create a double spend with Bitcoin Core using console commands. Also, since some nodes won't relay or accept transactions with low fees, changing the fee get the double spend accepted into some mempools when the original did not. Otherwise, nodes that enabled Replace-By-Fee will allow double spends as long as the fee is greater than the original and nodes that are Bitcoin XT will relay double spends.

turvarya

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Activity: 714

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I am not sure if this has been said in this thread, and it seems to be a lot of back and forth from the pages I read, so I figured I would just ask.

If I sent a transaction and didn't set the fee high enough, will the transaction eventually roll back? The BTC have left my wallet at this point, and it was for a paid service, so I am wondering if I have to worry about the transaction not going through.

It was through BitPay, so the vendor got their money I am sure, but I didn't know if the transaction itself would revert back because of the backlog.

The BTC has not really left your wallet until the transaction is included in a block (confirmed). It means you can 'override' your transaction, but it depends on your client.

Which client can "override" a transaction aka double spend it?
How do they trick the nodes, that just won't accept a double spend in their mempool?

RoadTrain

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Activity: 1386

Merit: 1009

SebastianJu, Xialla, I understand what you mean. You wanna say it's a Bitcoin problem, as if its adoption by everybody (even totally clueless) is the main goal. That's not what I want, because I like when people make educated decisions, especially about their money, that's why I disagree with you. Ok, that's understandable, it's an ideological disagreement, so no point in arguing.

RoadTrain

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Activity: 1386

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