The homebrew instructions were outdated - berkeley-db4 hasn't worked for months, based on the questions I'm seeing on Google/SO. So I added a section explaining how to install berkeley-db4 using homebrew and move on with your life. Thanks for the rest of the documentation!
Bitcoin core should work with any remotely recent boost version
if a proper build environment is present. Remove a confusing comment
from the build documentation.
Anyone building bitcoind/-qt on windows is welcome to contribute
a new one. The current information in this document is outdated,
or otherwise mostly worthless.
The wallet now uses the mempool fee estimator with a new
command-line option: -txconfirmtarget (default: 1) instead
of using hard-coded fees or priorities.
A new bitcoind that hasn't seen enough transactions to estimate
will fall back to the old hard-coded minimum priority or
transaction fee.
-paytxfee option overrides -txconfirmtarget.
Relaying and mining code isn't changed.
For Qt, the coin control dialog now uses priority estimates to
label transaction priority (instead of hard-coded constants);
unspent outputs were consistently labeled with a much higher
priority than is justified by the free transactions actually
being accepted into blocks.
I did not implement any GUI for setting -txconfirmtarget; I would
suggest getting rid of the "Pay transaction fee" GUI and replace
it with either "target number of confirmations" or maybe
a "faster confirmation <--> lower fee" slider or select box.
This is PR #4271, but with the changes to the descriptors, both the names of the
files and the names of the intermediate build artifact archives, removed.
This also closes#3775 if it goes in, because it covers the changes in
that PR.
New RPC methods: return an estimate of the fee (or priority) a
transaction needs to be likely to confirm in a given number of
blocks.
Mike Hearn created the first version of this method for estimating fees.
It works as follows:
For transactions that took 1 to N (I picked N=25) blocks to confirm,
keep N buckets with at most 100 entries in each recording the
fees-per-kilobyte paid by those transactions.
(separate buckets are kept for transactions that confirmed because
they are high-priority)
The buckets are filled as blocks are found, and are saved/restored
in a new fee_estiamtes.dat file in the data directory.
A few variations on Mike's initial scheme:
To estimate the fee needed for a transaction to confirm in X buckets,
all of the samples in all of the buckets are used and a median of
all of the data is used to make the estimate. For example, imagine
25 buckets each containing the full 100 entries. Those 2,500 samples
are sorted, and the estimate of the fee needed to confirm in the very
next block is the 50'th-highest-fee-entry in that sorted list; the
estimate of the fee needed to confirm in the next two blocks is the
150'th-highest-fee-entry, etc.
That algorithm has the nice property that estimates of how much fee
you need to pay to get confirmed in block N will always be greater
than or equal to the estimate for block N+1. It would clearly be wrong
to say "pay 11 uBTC and you'll get confirmed in 3 blocks, but pay
12 uBTC and it will take LONGER".
A single block will not contribute more than 10 entries to any one
bucket, so a single miner and a large block cannot overwhelm
the estimates.
Wladimir J. van der Laan