dataforge-labs/bitcoin-mempool-lifecycle

Bitcoin mempool lifecycle

Transactions from the moment they appear in the mempool to whatever happens to them: mined, still waiting, or dropped without ever reaching a block.

A confirmed transaction keeps its contents forever but loses its timing. One that is never mined leaves no record at all. Both are recorded here as they happen.

Contents

name	one row is
e8_btc_mempool_lifecycle	a Bitcoin transaction: first seen, fee rate, mined height, blocks waited, fate
e9_btc_mempool_divergence	one view of the pending set at one instant, sized and compared against the others
e11_ltc_mempool_lifecycle	the same, for Litecoin
e8_btc_block_composition	one block: how much of it we had already seen pending

Ethereum moved to its own repo, ethereum-mempool, rather than sitting inside a Bitcoin panel. Peer-to-peer propagation and relay floors likewise moved to bitcoin-network-propagation.

Fee rate coverage

fee_rate_sat_vb is present on a portion of rows and that portion changes over time. It is sampled, never estimated: a guessed fee rate would ruin the analyses the column exists for.

Coverage by day, as a share of transactions observed arriving (pre_existing == False):

date	coverage
2026-08-25	none
2026-08-26	~4%
2026-08-27	~14%
2026-08-28	~16% early, ~67% late
2026-08-29 onward	~67%

Coverage of transactions already pending when a collection window opened moved from about 1% to about 99% on 2026-08-28. Dropped rows inherit that figure and reached 94% on 2026-08-29.

Partitions from 2026-08-29 are substantially denser than earlier ones. Compute coverage per partition rather than assuming a constant:

obs = df[~df.pre_existing.astype(bool)]
coverage = obs.fee_rate_sat_vb.notna().mean()

Rows without a fee rate are complete in every other respect, so they remain usable for lifecycle work. Only fee-conditioned analysis is affected.

Reading the fate column

dropped means the transaction was confirmed absent from the chain, absent from every pending view held, and stayed absent through a debounce period. It is not inferred from a single observation. unresolved means it went missing but could not be confirmed, and is never counted as a drop.

Bitcoin fate = "dropped" begins 2026-08-26. Earlier partitions contain no drops because a defect made them impossible to record, not because none occurred.

How much of a block did we already know about

e8_btc_block_composition counts, for every block, how many of its transactions were already in our mempool view and how many appeared for the first time in the block itself.

The second number is the interesting one. A transaction that reaches a miner without crossing the public relay network looks exactly like this, which is what direct-to-pool submission is. So does a transaction broadcast in the seconds between two of our polls, and so does one our providers simply never held. The column is therefore an upper bound on out-of-band submission, not a measurement of it, and polls_so_far, poll_failures and pool_size_at_block travel on every row so the bound can be tightened or discarded.

It doubles as a coverage statement for the rest of this repo. If you want to know how complete the mempool view behind e8_btc_mempool_lifecycle is, this is the answer, block by block, in the data rather than in a claim. One observed block held 4,823 transactions excluding the coinbase, of which 4,804 were already in view: 99.6% captured, and 19 seen for the first time in the block itself.

The coinbase is excluded, since it is created by the miner and never broadcast; counting it would add one guaranteed unseen transaction to every block. Blocks mined before a run's baseline was established are not recorded at all, because none of their transactions could have been seen and the row would read 100% unseen for a reason that has nothing to do with the network.

Package fee rates

A transaction's own fee rate is not what decides whether it is mined. A miner sorts by the ANCESTOR fee rate, so a transaction with an unconfirmed low-fee parent is worth less than it appears, and a child paying a large fee lifts its parent with it.

effective_fee_rate_sat_vb is ancestor_fees_sat / ancestor_vsize. For a transaction with no unconfirmed parents it equals fee_rate_sat_vb exactly; where they diverge, the effective rate is the one that governs inclusion. One snapshot held a transaction paying 28.4 sat/vB whose effective rate was 2.1.

ancestor_count above 1 marks membership in an unconfirmed chain, which is how fee bumping by a child shows up. The descendant columns are the mirror: what is waiting on this transaction.

These come from a full node's own view, so they are null for transactions it never held, and they are recorded as first observed. Package structure changes as parents confirm, so treat them as the state at first sight rather than a running value.

Before you build on this

• Pending sets are node-local. What one view holds is not what the network holds, and retention is a configuration choice rather than a protocol rule. e9 exists to size that disagreement, and it is large: at one instant the views ranged from about 6,000 to about 87,000 pending transactions, with only 7% common to all of them.
• Dropped rows carry a fee rate far less often than mined rows. Every drop observed so far was already pending when its window opened, and fee sampling favours arrivals.
• A fee rate of exactly 0 is real and rare. Filter on fee_rate_sat_vb > 0 if a zero would break your arithmetic rather than treating it as a decode fault.
• Timestamps are ours, taken at observation. They are not consensus timestamps and carry our network distance to whatever served the data.

Partitions are parquet, one file per collection window, under dataset/YYYY/MM/. Every dataset here carries a FIXED 7-day sample WINDOW starting at its own first day of collection, together spanning 2026-08-25 to 2026-09-05, so you can check schema, coverage and quality before asking for more. It does not advance, so there is nothing to gain by re-downloading it. The full history is held privately, available on request.

from huggingface_hub import snapshot_download
import pandas as pd, glob

path = snapshot_download("dataforge-labs/bitcoin-mempool-lifecycle", repo_type="dataset",
                         allow_patterns="e8_btc_mempool_lifecycle/**")
df = pd.concat(map(pd.read_parquet,
                   glob.glob(f"{path}/e8_btc_mempool_lifecycle/**/*.parquet", recursive=True)))

Coverage

e0_run_manifest lists every collection window with its poll counts and failure counts, and is published in full rather than windowed. Gaps between windows are real, cannot be filled in afterwards, and nothing here is interpolated.

License and contact

ODC-BY: use it freely, credit "DataForge (dataforge-labs)". Questions and requests for the full history via the discussions tab.