Bitcoin Forum

Antpool is a mining pool that also runs a free prioritisation service. The service requires a user account. Not all prioritisation requests are successful, but some are, so it might be worth trying. Here’s how:

• Have a working email address and phone number.
• Browse to https://www.antpool.com/user/prioritiseTransaction.htm. This is the prioritisation page, so you may want to bookmark it. Since you probably don’t have an account yet, click ‘Sign up’, and go through the account creation process.
• When you have created your account, browse to the prioritisation page and sign in. Change the language if you want. You should see a page with two text areas. The upper one is for transaction IDs. Paste yours there, one per row. Ignore the lower text field. Solve the captcha and click ‘Submit’. You should now see your transactions in a list at the bottom of the page.

You can follow blocks mined by Antpool at https://blockchain.info/blocks/AntPool.

If you’re unable to create an account on Antpool, please post your transaction ID below, and I or someone else may be able to enter your request for you. I would also love to hear your experiences with the Antpool prioritisation service: what kind of transactions end up being successfully mined? I have used the service only a few times so far.

Edit: There's a comprehensive guide on 'stuck' transactions at https://bitcointalk.org/index.php?topic=1802212.

7a9532803a68c995de2d1b269f765bccc61253cc27930a216ac0dea4d66baa93

unable to open an account. would you do stg for this one? waiting for days. thanks.

Added to the Antpool list. But your fee is very low considering the amount of inputs, so I nevertheless doubt your transaction will be mined shortly if at all. If you can do a RBF or CPFP, that might be a good idea. Advice here: https://bitcointalk.org/index.php?topic=1802212

Prior to recent spike of unconfirmed transactions (around 2 months ago) I was able to accelerate transactions that contained only 1.5 sat/B in transaction fees but it's no longer the case (either due to the fact that it became a known service or they change its structure completely).
Nowadays only those transactions that underpaid by around 100+ sat/B (based on this website (https://bitcoinfees.earn.com/#fees)) are being included in next blocks that they mine (considering those have been accelerated through Antpool), meaning they prioritize transactions based on their fees (on their queue list) so it wouldn't be that useful (if it's urgent) for majority of transactions that use a very low fee (those with less than 250 sat/B) since the list gets updated frequently with other added transactions.

This is correct...
Due to people posting the link to that page on bitcointalk and other public pages, i can only assume their acceleration page gets spammed by hundreds of people that want to cheap out on their fees and push a 1 sat/byte tx in antpool's blocks.

I can only assume antpool uses their mining node's prioritisetransaction funtion. If all prioritised transactions get the same fee_delta, it would still lead to a fee bidding war within the prioritised transactions in their mempool.
Even worse, if their (hypotetical) fee delta is, for example 50 sat/byte, a transaction with a 1 sat/byte fee that gets prioritised would still only have a virtual fee of 51 sat/byte, hence have little or no chance of being put in antpool's blocks, since there are enougn non-prioritised transaction that have a much higher fee.

I have no idear if this is the way antpool works, but this hypothesis seems to be more or less consistent with what i'm seeing trough the use of their accelerator page.

So in a way, one could argue that ‘acceleration’ services are harmful in the long run and that users should be more responsible about including sufficient fees in the first place. Hopefully the problem will be alleviated through technologies such as RBF and through better user interfaces. Alhough based on the requests I see here, it seems many insufficiently funded transactions are sent by exchanges and other senders that should know better :o

I think acceleration services started out with anyway self-promotional motivations. ViaBTC, for example, loaded up that "manifesto" page in the months prior to the Bitcoin Cash fork. They may have helped a lot of people who unwittingly used low fee transactions, but yeah, after all these free services became known, I think people just used them to skimp on fees. You could say this just delayed the application of "correct" behaviour when it comes to spending coins, in a way cheating others who actually use good fees and maintain good wallet practises.

As you say though, exchanges and other site-based wallets are themselves not using high-enough fees, and I can perfectly understand people use these acceleration services since they have no control over withdrawals processed from these sites. That's my own personal experience too, spending coins from a web service that ended up with a 400 sat/byte fee during the 300k mempool days. I accelerated that on antpool and it got confirmed in 2 days (estimator said 3 days), so I'm assuming it still works.

I've also now stopped accelerating for most people. I think a lot of us have been duped by newbie accounts feigning ignorance and asking for low-fee txs to be accelerated.

Theories about antpool: probably correct. They still accept valid tx IDs, so they must also have a queue that's virtually a mempool within a mempool. With its own (less severe) fee prioritisation.