33b12e5df6 docs: improve docs where MemPoolLimits is used (stickies-v)
6945853c0b test: use NoLimits() in MempoolIndexingTest (stickies-v)
3a86f24a4c refactor: mempool: use CTxMempool::Limits (stickies-v)
b85af25f87 refactor: mempool: add MemPoolLimits::NoLimits() (stickies-v)
Pull request description:
Mempool currently considers 4 limits regarding ancestor and descendant count and size, which get passed around between functions quite a bit. This PR uses `CTxMemPool::Limits` introduced in https://github.com/bitcoin/bitcoin/pull/25290 to simplify those signatures and callsites.
The purpose of this PR is to improve readability and maintenance, without behaviour change.
As noted in the first commit "refactor: mempool: change MemPoolLimits members to uint", we currently have an underflow issue where a user could pass a negative `-limitancestorsize`, which is eventually cast to an unsigned integer. This behaviour already exists. Because it's orthogonal and to minimize scope, I think this should be fixed in a separate PR.
ACKs for top commit:
hebasto:
ACK 33b12e5df6, I have reviewed the code and it looks OK, I agree it can be merged.
glozow:
reACK 33b12e5df6
Tree-SHA512: 591c6dcee1894f1c3ca28b34a680eeadcf0d40cda92451b4a422c03087b27d682b5e30ba4367abd75a99b5ccb115b7884b0026958d3c7dddab030549db5a4056
Simplifies function signatures by removing repetition of all the
ancestor/descendant limits, and increases readability by being
more verbose by naming the limits, while still reducing the LoC.
m_is_loaded/IsLoaded() doesn't actually indicate whether or not the
mempool was successfully, loaded, but rather if a load has been
attempted and did not result in a catastrophic ShutdownRequested.
-BEGIN VERIFY SCRIPT-
find_regex="\bm_is_loaded\b" \
&& git grep -l -E "$find_regex" \
| xargs sed -i -E "s@$find_regex@m_load_tried@g"
find_regex="\bIsLoaded\b" \
&& git grep -l -E "$find_regex" \
| xargs sed -i -E "s@$find_regex@GetLoadTried@g"
find_regex="\bSetIsLoaded\b" \
&& git grep -l -E "$find_regex" \
| xargs sed -i -E "s@$find_regex@SetLoadTried@g"
-END VERIFY SCRIPT-
This new node policy setting enables to accept replaced-by-fee
transaction without inspection of the replaceability signaling
as described in BIP125 "explicit signaling".
If turns on, the node mempool accepts transaction replacement
as described in `policy/mempool-replacements.md`.
The default setting value is `false`, implying opt-in RBF
is enforced.
d1684beabe fees: Pass in a filepath instead of referencing gArgs (Carl Dong)
9a3d825c30 init: Remove redundant -*mempool*, -limit* queries (Carl Dong)
6c5c60c412 mempool: Use m_limit for UpdateTransactionsFromBlock (Carl Dong)
9e93b10301 node/ifaces: Use existing MemPoolLimits (Carl Dong)
38af2bcf35 mempoolaccept: Use limits from mempool in constructor (Carl Dong)
9333427014 mempool: Introduce (still-unused) MemPoolLimits (Carl Dong)
716bb5fbd3 scripted-diff: Rename anc/desc size limit vars to indicate SI unit (Carl Dong)
1ecc77321d scripted-diff: Rename DEFAULT_MEMPOOL_EXPIRY to indicate time unit (Carl Dong)
aa9141cd81 mempool: Pass in -mempoolexpiry instead of referencing gArgs (Carl Dong)
51c7a41a5e init: Only determine maxmempool once (Carl Dong)
386c9472c8 mempool: Make GetMinFee() with custom size protected (Carl Dong)
82f00de7a6 mempool: Pass in -maxmempool instead of referencing gArgs (Carl Dong)
f1941e8bfd pool: Add and use MemPoolOptions, ApplyArgsManOptions (Carl Dong)
0199bd35bb fuzz/rbf: Add missing TestingSetup (Carl Dong)
ccbaf546a6 scripted-diff: Rename DEFAULT_MAX_MEMPOOL_SIZE to indicate SI unit (Carl Dong)
fc02f77ca6 ArgsMan: Add Get*Arg functions returning optional (Carl Dong)
Pull request description:
This is part of the `libbitcoinkernel` project: #24303, https://github.com/bitcoin/bitcoin/projects/18
-----
As mentioned in the Stage 1 Step 2 description of [the `libbitcoinkernel` project](https://github.com/bitcoin/bitcoin/issues/24303), `ArgsManager` will not be part of `libbitcoinkernel`. Therefore, it is important that we remove any dependence on `ArgsManager` by code that will be part of `libbitcoinkernel`. This is the first in a series of PRs aiming to achieve this.
This PR removes `CTxMemPool+MempoolAccept`'s dependency on `ArgsManager` by introducing a `CTxMemPool::Options` struct, which is used to specify `CTxMemPool`'s various options at construction time.
These options are:
- `-maxmempool` -> `CTxMemPool::Options::max_size`
- `-mempoolexpiry` -> `CTxMemPool::Options::expiry`
- `-limitancestorcount` -> `CTxMemPool::Options::limits::ancestor_count`
- `-limitancestorsize` -> `CTxMemPool::Options::limits::ancestor_size`
- `-limitdescendantcount` -> `CTxMemPool::Options::limits::descendant_count`
- `-limitdescendantsize` -> `CTxMemPool::Options::limits::descendant_size`
More context can be gleaned from the commit messages. The important commits are:
- 56eb479ded8bfb2ef635bb6f3b484f9d5952c70d "pool: Add and use MemPoolOptions, ApplyArgsManOptions"
- a1e08b70f3068f4e8def1c630d8f50cd54da7832 "mempool: Pass in -maxmempool instead of referencing gArgs"
- 6f4bf3ede5812b374828f08fc728ceded2f10024 "mempool: Pass in -mempoolexpiry instead of referencing gArgs"
- 5958a7fe4806599fc620ee8c1a881ca10fa2dd16 "mempool: Introduce (still-unused) MemPoolLimits"
Reviewers: Help needed in the following commits (see commit messages):
- a1e08b70f3068f4e8def1c630d8f50cd54da7832 "mempool: Pass in -maxmempool instead of referencing gArgs"
- 0695081a797e9a5d7787b78b0f8289dafcc6bff7 "node/ifaces: Use existing MemPoolLimits"
Note to Reviewers: There are perhaps an infinite number of ways to architect `CTxMemPool::Options`, the current one tries to keep it simple, usable, and flexible. I hope we don't spend too much time arguing over the design here since that's not the point. In the case that you're 100% certain that a different design is strictly better than this one in every regard, please show us a fully-implemented branch.
-----
TODO:
- [x] Use the more ergonomic `CTxMemPool::Options` where appropriate
- [x] Doxygen comments for `ApplyArgsManOptions`, `MemPoolOptions`
-----
Questions for Reviewers:
1. Should we use `std::chrono::seconds` for `CTxMemPool::Options::expiry` and `CTxMemPool::m_expiry` instead of an `int64_t`? Something else? (`std::chrono::hours`?)
2. Should I merge `CTxMemPool::Limits` inside `CTxMemPool::Options`?
ACKs for top commit:
MarcoFalke:
ACK d1684beabe🍜
ryanofsky:
Code review ACK d1684beabe. Just minor cleanups since last review, mostly switching to brace initialization
Tree-SHA512: 2c138e52d69f61c263f1c3648f01c801338a8f576762c815f478ef5148b8b2f51e91ded5c1be915e678c0b14f6cfba894b82afec58d999d39a7bb7c914736e0b
Since:
- UpdateTransactionsFromBlock is only called by
MaybeUpdateMempoolForReorg, which calls it with the gArgs-determined
ancestor limits
- UpdateForDescendants is only called by UpdateTransactionsFromBlock
with the ancestor limits unchanged
We can remove the requirement to specify the ancestor limits for both
UpdateTransactionsFromBlock and UpdateForDescendants and just use the
values in the m_limits member.
Also move some removed comments to MemPoolLimits struct members.
The uint64_t cast in UpdateForDescendants is not new behavior,
see the diff in CChainState::MaybeUpdateMempoolForReorg for where they
were previously.
- Store the mempool expiry (-mempoolexpiry) in CTxMemPool as a
std::chrono::seconds member.
- Remove the requirement to explicitly specify a mempool expiry for
LimitMempoolSize(...), just use the newly-introduced member.
- Remove all now-unnecessary instances of:
std::chrono::hours{gArgs.GetIntArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY)}
- Store the mempool size limit (-maxmempool) in CTxMemPool as a member.
- Remove the requirement to explicitly specify a mempool size limit for
CTxMemPool::GetMinFee(...) and LimitMempoolSize(...), just use the
stored mempool size limit where possible.
- Remove all now-unnecessary instances of:
gArgs.GetIntArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE_MB) * 1000000
The code change in CChainState::GetCoinsCacheSizeState() is correct
since the coinscache should not repurpose "extra" mempool memory
headroom for itself if the mempool doesn't even exist.
Reviewers: Note that CTxMemPool now requires a non-defaulted
CTxMemPool::Options for its constructor. Meaning that there's no need to
worry about a stray CTxMemPool constructor somewhere defaulting to
something incorrect. All instances of CTxMemPool construction are
addressed here in this commit.
We set options for CTxMemPool and construct it in many different ways. A
good example can be seen in how we determine CTxMemPool's check_ratio in
AppInitMain(...).
1. We first set the default based on chainparams's
DefaultConsistencyChecks()
2. Then, we apply the ArgsManager option on top of that default
3. Finally, we clamp the result of that between 0 and 1 Million
With this patch, most CTxMemPool construction are along the lines of:
MemPoolOptions mempool_opts{...default overrides...};
ApplyArgsManOptions(argsman, mempool_opts);
...hard overrides...
CTxMemPool pool{mempool_opts};
This "compositional" style of building options means that we can omit
unnecessary/irrelevant steps wherever we want but also maintain full
customizability.
For example:
- For users of libbitcoinkernel, where we eventually want to remove
ArgsManager, they simply won't call (or even know about)
ApplyArgsManOptions.
- See src/init.cpp to see how the check_ratio CTxMemPool option works
after this change.
A MemPoolOptionsForTest helper was also added and used by tests/fuzz
tests where a local CTxMemPool needed to be created.
The change in src/test/fuzz/tx_pool.cpp seemingly changes behaviour by
applying ArgsManager options on top of the CTxMemPool::Options defaults.
However, in future commits where we introduce flags like -maxmempool,
the call to ApplyArgsManOptions is actually what preserves the existing
behaviour. Previously, although it wasn't obvious, our CTxMemPool would
consult gArgs for flags like -maxmempool when it needed it, so it
already relied on ArgsManager information. This patchset just laid bare
the obfuscatory perils of globals.
[META] As this patchset progresses, we will move more and more
CTxMemPool-relevant options into MemPoolOptions and add their
ArgsMan-related logic to ApplyArgsManOptions.
* feeDelta tracked the delta (to be applied on top of the actual fee)
* m_modified_fee tracks the actual fee with the delta included
* Instead of passing in the new total delta to the Updater, pass in by
how much the total delta should be modified.
This is needed for the next commit, but makes sense on its own because
the same is done by UpdateDescendantState and UpdateAncestorState.
fa32cc0682 doc: Remove fee delta TODO from txmempool.cpp (MarcoFalke)
Pull request description:
This refactor request was added in commit eb306664e7, though it didn't explain why the refactor is needed and what the goal is. Given that this wasn't touched for more than 5 years, it doesn't seem critical. Generally, non-trivial `TODO`s make more sense as GitHub issues, so that they can be discussed and triaged more easily.
ACKs for top commit:
laanwj:
Code review ACK fa32cc0682
Tree-SHA512: 6629fef543e815136c82c38aa8ba2c4de68a5fe94c6954f2559e468f7e59052e02dd7c221d3b159be0314eaf0dbb18f74814297c58f76e2289c47e8d4f49be4e
9d65ad365c Clear vTxHashes when mapTx is cleared (Peter Bushnell)
Pull request description:
vTxHashes is a vector of all entries in mapTx, if you clear one you should clear the other, lest someone try to use the txiter in vTxHashes which would result in a segfault.
ACKs for top commit:
laanwj:
Code review ACK 9d65ad365c
Tree-SHA512: 6832755e43ab7f528b46817aeadcb6ffdc965b97f59ab96bb053dedbb7e68155ba3db52286355dca33b509237f80eda249760b26db493762bc50d8e2cef16d8f
c5b36b1c1b Mempool Update Cut-Through Optimization (Jeremy Rubin)
c49daf9885 [TESTS] Increase limitancestorcount in tournament RPC test to showcase improved algorithm (Jeremy Rubin)
Pull request description:
Often when we're updating mempool entries we update entries that we ultimately end up removing the updated entries shortly thereafter. This patch makes it so that we filter for such entries a bit earlier in processing, which yields a mild improvement for these cases, and is negligible overhead otherwise.
There's potential for a better -- but more sophisticated -- algorithm that can be used taking advantage of epochs, but I figured it is better to do something that is simple and works first and upgrade it later as the other epoch mempool work proceeds as it makes the patches for the epoch algorithm simpler to understand, so you can consider this as preparatory work. It could either go in now if it is not controversial, or we could wait until the other patch is ready to go.
ACKs for top commit:
instagibbs:
reACK c5b36b1
sipa:
utACK c5b36b1c1b
mzumsande:
Code Review ACK c5b36b1c1b
Tree-SHA512: 78b16864f77a637d8a68a65e23c019a9757d8b2243486728ef601d212ae482f6084cf8e69d810958c356f1803178046e4697207ba40d6d10529ca57de647fae6
b4adc5ad67 [bugfix] update lockpoints correctly during reorg (glozow)
b6002b07a3 MOVEONLY: update_lock_points to txmempool.h (glozow)
Pull request description:
I introduced a bug in #22677 (sorry! 😅)
Mempool entries cache `LockPoints`, containing the first height/blockhash/`CBlockIndex*` at which the transaction becomes valid. During a reorg, we re-check timelocks on all mempool entries using `CheckSequenceLocks(useExistingLockPoints=false)` and remove any now-invalid entries. `CheckSequenceLocks()` also mutates the `LockPoints` passed in, and we update valid entries' `LockPoints` using `update_lock_points`. Thus, `update_lock_points(lp)` needs to be called right after `CheckSequenceLocks(lp)`, otherwise we lose the data in `lp`. I incorrectly assumed they could be called in separate loops.
The incorrect behavior introduced is: if we have a reorg in which a timelocked mempool transaction is still valid but becomes valid at a different block, the cached `LockPoints` will be incorrect.
This PR fixes the bug, adds a test, and adds an assertion at the end of `removeForReorg()` to check that all mempool entries' lockpoints are valid. You can reproduce the bug by running the test added in the [test] commit on the code before the [bugfix] commit.
ACKs for top commit:
jnewbery:
ACK b4adc5ad67
vasild:
ACK b4adc5ad67
mzumsande:
Code Review ACK b4adc5ad67
hebasto:
ACK b4adc5ad67
MarcoFalke:
re-ACK b4adc5ad67🏁
Tree-SHA512: 16b59f6ff8140d0229079ca1c6b04f2f4a00a2e49931275150e4f3fe5ac4ec109698b083fa6b223ba9511f328271cc1ab081263669d5da020af7fee83c13e401
Often when we're updating mempool entries we update entries that we
ultimately end up removing the updated entries shortly thereafter. This
patch makes it so that we filter for such entries a bit earlier in
processing, which yields a mild improvement for these cases, and is
negligible overhead otherwise.
During a reorg, we re-check timelocks on all mempool entries using
CheckSequenceLocks(useExistingLockPoints=false) and remove any
now-invalid entries. CheckSequenceLocks() also mutates the LockPoints
passed in, and we update valid entries' LockPoints using
update_lock_points. Thus, update_lock_points(lp) needs to be called
right after CheckSequenceLocks(lp), otherwise we lose the data in lp.
commit bedf246 introduced a bug by separating those two loops.
No behavior change.
Parameterize removeForReorg using a CChain and callable that
encapsulates validation logic. The mempool shouldn't need to know a
bunch of details about coinbase maturity and lock finality. Instead,
just pass in a callable function that says true/false. Breaks circular
dependency by removing txmempool's dependency on validation.
Each entry's lockpoints are independent of one another, so there isn't
any reason to update lockpoints for entries that will be removed.
Separating the loops also allows us to move validation logic out and
leave lockpoints in txmempool.
65aaf9495d refactor: move `update_*` structs from txmempool.h to .cpp file (Sebastian Falbesoner)
9947ce6262 refactor: use const reference for parents in `CTxMemPool::UpdateAncestorsOf` (Sebastian Falbesoner)
Pull request description:
These helpers are exclusively used in txmempool.cpp, hence they should also be moved there. The PR also contains a commit which fixes const-correctness for parents in `CTxMemPool::UpdateAncestorsOf` and declares them as reference to avoid a copy.
ACKs for top commit:
promag:
Code review ACK 65aaf9495d. Verified move-only commit locally.
Tree-SHA512: 7ce29f3ba0e68b5355001f27725b00f6d54cc993015356eb40b61b8cdd17db49b980f4c3d798c8e0c940d245dc3a72c474bb9ff3c0ee971ead450786076812c2
082c5bf099 [refactor] pass coinsview and height to check() (glozow)
ed6115f1ea [mempool] simplify some check() logic (glozow)
9e8d7ad5d9 [validation/mempool] use Spend/AddCoin instead of UpdateCoins (glozow)
09d18916af MOVEONLY: remove single-use helper func CheckInputsAndUpdateCoins (glozow)
e8639ec26a [mempool] remove now-unnecessary code (glozow)
54c6f3c1da [mempool] speed up check() by using coins cache and iterating in topo order (glozow)
30e240f65e [bench] Benchmark CTxMemPool::check() (glozow)
cb1407196f [refactor/bench] make mempool_stress bench reusable and parameterizable (glozow)
Pull request description:
Remove the txmempool <-> validation circular dependency by removing txmempool's dependency on validation. There are two functions in txmempool that need validation right now: `check()` and `removeForReorg()`. This PR removes the dependencies in `check()`.
This PR also improves the performance of `CTxMemPool::check()` by walking through the entries exactly once, in ascending ancestorcount order, which guarantees that we see parents before children.
ACKs for top commit:
jnewbery:
reACK 082c5bf099
GeneFerneau:
tACK [082c5bf](082c5bf099)
rajarshimaitra:
tACK 082c5bf099
theStack:
Code-review ACK 082c5bf099
Tree-SHA512: 40ac622af1627b5c3e6abb4f0f035d833265a8c5e8dc88faf5354875dfb5137f137825e54bbd2a2668ed37b145c5d02285f776402629f58596e51853a9a79d29
No transaction in the mempool should ever be a coinbase.
Since mempoolDuplicate's backend is the chainstate coins view, it should
always contain the coins available.
UpdateCoins is an unnecessary dependency on validation. All we need to
do is add and remove coins to check inputs. We don't need the extra
logic for checking coinbases and handling TxUndos.
Also remove the wrapper function in validation.h which constructs a
throwaway TxUndo object before calling UpdateCoins because it is now
unused.
