ZIP 239 preparations 2
Cherry-picked from the following upstream PRs:
- bitcoin/bitcoin#6722
- Only the ancillary commits, not the mempool limiting commits (we have our own).
- bitcoin/bitcoin#6898
- Only the first three commits (we'll cherry-pick the main content later).
- bitcoin/bitcoin#7840
Also remove the RPC deprecation tests for accounts, and make one small
change to another wallet test that relies on account behaviour.
(cherry picked from commit f0dc850bf698f7377797d7d68365d4fc79b0221c)
Previously Bitcoin would send 1/4 of transactions out to all peers
instantly. This causes high overhead because it makes >80% of
INVs size 1. Doing so harms privacy, because it limits the
amount of source obscurity a transaction can receive.
These randomized broadcasts also disobeyed transaction dependencies
and required use of the orphan pool. Because the orphan pool is
so small this leads to poor propagation for dependent transactions.
When the bypass wasn't in effect, transactions were sent in the
order they were received. This avoided creating orphans but
undermines privacy fairly significantly.
This commit:
Eliminates the bypass. The bypass is replaced by halving the
average delay for outbound peers.
Sorts candidate transactions for INV by their topological
depth then by their feerate (then hash); removing the
information leakage and providing priority service to
higher fee transactions.
Limits the amount of transactions sent in a single INV to
7tx/sec (and twice that for outbound); this limits the
harm of low fee transaction floods, gives faster relay
service to higher fee transactions. The 7 sounds lower
than it really is because received advertisements need
not be sent, and because the aggregate rate is multipled
by the number of peers.
(cherry picked from commit f2d3ba73860e875972738d1da1507124d0971ae5)
Zcash: Candidate transactions for INV are not sorted by their
topological depth because we haven't backported bitcoin/bitcoin#6654.
ZIP 239 preparations 1
This is the first of several backports to prepare for ZIP 239. The primary
change is altering `mapRelay` to store `CTransaction`s, which we need
because ZIP 239 requires changing `Inv` messages based on transaction
versions. The other changes are mainly for conflict removal but are also
independently useful.
Backports the following upstream PRs:
- bitcoin/bitcoin#6889
- bitcoin/bitcoin#7125
- bitcoin/bitcoin#7862
- bitcoin/bitcoin#7877
The recent changes to mempool inv logic mean that nodes are much less
likely to immediately return an `inv` message in response to a `mempool`
message. The `p2p_txexpiringsoon` RPC test was relying on the prior
behaviour.
`TestNode.sync_with_ping` now takes an optional `waiting_for` closure
that allows the caller to require that a specific message kind is
received prior to the timeout.
Previously these functions would infinitely loop if sync failed;
now they have a default timeout of 60 seconds, after which an
AssertionError is raised.
sync_blocks() has also been improved and now compares the tip
hash of each node, rather than just using block count.
Zcash: Kept block count check for a couple of tests where we use it.