5 votes
Accepted

How does getblocktemplate select transactions?

The whole mempool won't fit in a block; getblocktemplate returns enough transactions for a block. Blocks are, by default, limited to 750kb by policy, but many miners increase the size to the block ...
fluffyponyza's user avatar
4 votes
Accepted

Why does getblocktemplate use priority for transaction selection?

Getblocktemplate builds a block based on configuration parameters. In recent versions, the default is to use fee per byte as criterion for the entire block. History In versions of Bitcoin up to 0.6, ...
Pieter Wuille's user avatar
4 votes

What were 'high-priority' transactions in Bitcoin Core v0.9?

Historically it was not required to include a fee for every transaction. A large portion of miners would mine transactions with no fee given that they had enough "priority". Today, low priority is ...
Haseeb Saeed's user avatar
3 votes

What are the arguments for and against deprecating transaction priority?

Since transaction priority has never really been a consensus based "protocol", it was never really that valuable to have it in the core code. Miners can and DO change the priority how they see fit. I ...
Paul Puey's user avatar
3 votes
Accepted

What were 'high-priority' transactions in Bitcoin Core v0.9?

Priority was calculated based on the age of the inputs. Older and larger inputs were given a higher priority than new and low valued inputs. This allowed transactions to pay no transaction fees but ...
Ava Chow's user avatar
  • 70.5k
3 votes

Why is the transaction priority removed?

Firstly, the priority mechanism was not a consensus rule. Originally it was just a few hundred kilobytes of space reserved in a block (100 kb IIRC) for transactions that had a high priority. But this ...
Ava Chow's user avatar
  • 70.5k
3 votes
Accepted

Is it OK not to sort transactions at all?

As long as all selected transactions are valid, you may select any transactions you want. You should check that there are no double spends among the selected transactions and that you keep any ...
Murch's user avatar
  • 75.4k
2 votes
Accepted

Mined blocks with reserved space for old utxos

Ok. I've found this: https://www.linkedin.com/pulse/what-high-priority-transaction-tara-annison, check out the comments since they have useful links. It seems 50kb of block space was reserved for high ...
dev7ba's user avatar
  • 373
2 votes
Accepted

Are any miners still considering priority in their transaction selection?

Generally, no miners still use the priority system for selecting transactions. You can easily test this by spending a very old UTXO (e.g. 1 BTC that has remained unspent for several years) and paying ...
Ava Chow's user avatar
  • 70.5k
2 votes
Accepted

How is the prioritization of Bitcoin Transactions done as of today?

The (close-to┬╣) highest block reward is achieved by including the transactions with the highest fee per weight. Deviating from that, miners are free to include any valid transactions at whim. They may ...
Murch's user avatar
  • 75.4k
2 votes

As a solo miner how can I prioritize my own unconfirmed transactions?

With 150GH/s, at the time of writing, you would find one block every 1500 years. That means if you were solo mining, you'd be able to control the contents of a block once every 1500 years. Or in ...
Pieter Wuille's user avatar
2 votes
Accepted

As a solo miner how can I prioritize my own unconfirmed transactions?

If you are the pool itself, or are solo mining you can use the prioritisetransaction command to add weight to your own transaction, if you are a client of a pool you do not have any control over what ...
Claris's user avatar
  • 15.4k
2 votes

Why is the transaction priority removed?

Selection by "age x value" creates an arbitrary nobility for early adopters/large hodlers. Early adopters having old coins would be able to cut in line any time, large hodlers could cut in line by ...
Murch's user avatar
  • 75.4k
2 votes
Accepted

Will Bitcoin remember unperformed transactions?

First of all: there's no guarantee that it will be free after 15 days. Some miners used to have a policy that made spending old coins potentially free. But miners can change those policies and will ...
Jannes's user avatar
  • 6,344
2 votes

Can zero-fee txs get into a block?

Zero-fee transactions are permitted by the protocol rules, but there is no incentive to give away block space without getting paid for it. Generally zero-fee transactions are a thing of the past since ...
Murch's user avatar
  • 75.4k

Only top scored, non community-wiki answers of a minimum length are eligible