1404c57403 [doc] Coin: explain that IsSpent() can also mean never existed (Sjors Provoost)
Pull request description:
This can be especially confusing where `AccessCoin()` is used with logic like this:
```c++
while (iter.n < MAX_OUTPUTS_PER_BLOCK) {
const Coin& alternate = view.AccessCoin(iter);
if (!alternate.IsSpent()) return alternate;
```
ACKs for top commit:
practicalswift:
ACK 1404c57403
MarcoFalke:
ACK 1404c57403
jnewbery:
utACK 1404c57403
Tree-SHA512: 418618dd7e08bd5cc8360e3501d0f57e34100e5101ad3b8e0a819923fa860f44c7f2fada0f8447a1af3c2601fd72bfe619b91ff2f26f7133ceaeb0c98b017b12
Move the hashers that we use for hash tables to a common place.
Moved hashers:
- SaltedTxidHasher
- SaltedOutpointHasher
- FilterHeaderHasher
- SignatureCacheHasher
- BlockHasher
Also adds CCoinsViewCache::ReallocateCache() to attempt to free
memory that the cacheCoins's allocator may be hanging onto when
downsizing the cache.
Adds `CChainState::m_coins{tip,db}_cache_size_bytes` data members
so that we can reference cache size on a per-chainstate basis for
flushing.
fa09110ebb doc: Fix typo in Coin doxygen comment (MarcoFalke)
Pull request description:
`CTxOutCompressor` has been renamed in commit 4de934b9b5, so rename it in the docs as well.
ACKs for top commit:
laanwj:
ACK fa09110ebb
hebasto:
ACK fa09110ebb
Tree-SHA512: e16a21ac3112a67ee7d5ffabb3f47103aed8f91fdebf1bf96311cd0b7bdb9b7323ed826bfa95517386d4128ff0ae2c7c13bad047a7c5a0cc2458be7a43119157
21fa0a44ab [docs] use consistent naming for possible_overwrite (John Newbery)
2685c214cc [tests] small whitespace fixup (John Newbery)
e9936966c0 scripted-diff: Rename PRUNED to SPENT in coins tests (John Newbery)
c205979031 [docs] Improve commenting in coins.cpp|h (John Newbery)
Pull request description:
- Add full commenting for spentness / DIRTYness / FRESHness and which combinations are valid
- Remove the 'pruned' terminology, which doesn't make sense since per-txout chainstate db was merged (#10195).
- Rename `potential_overwrite` to `possible_overwrite` to standardize terminology (there were previously examples of both, which made searching the codebase difficult).
- Make other minor improvements to the comments
ACKs for top commit:
jonatack:
Re-ACK 21fa0a4 per `git diff 98bee55 21fa0a4` the only change since my previous review is the following code commenting diff in `src/coins.cpp::L177-179`; rebuilt/ran unit tests anyway as a sanity check on the unit test changes.
Tree-SHA512: 391e01588ef5edb417250080cec17361f982c4454bc5f8c6d78bbd528c68a2bb94373297760691295c24660ce1022ad3ef7599762f736c8eed772ce096d38c3d
If the hash is not noexcept, unorderd_map has to assume that it can throw an exception. Thus when rehashing care needs to be taken. libstdc++ solves this by simply caching the hash value, which increases memory of each node by 8 bytes. Adding noexcept prevents this caching. In my experiments with -reindex-chainstate -stopatheight=594000, memory usage has decreased by 9.4% while runtime has increased by 1.6% due to additional hashing. Additionally, memusage::DynamicUsage() is now more accurate and does not underestimate.
and into coins.cpp. This move is necessary so that we can later include a
CCoinsViewErrorCatcher instance under CChainState.
Co-authored-by: MarcoFalke <falke.marco@gmail.com>
5d26205272 doc: explain AcceptToMemoryPoolWorker's coins_to_uncache (James O'Beirne)
Pull request description:
I found ATMPW's `coins_to_uncache` a little hard to understand (see #15264). This adds some doc for posterity.
ACKs for commit 5d2620:
jnewbery:
ACK 5d26205272
Tree-SHA512: 088508fa78012fab8680663c4e30f5cee29768416c2ca8b8b2abc29b6ac7067c5a589674f0254474a7ccc95477889d41719760f5796792bf492f51b3dd499c6c
Currently RPC commands are formatted in a way that it's easy to read
and that test/lint/check-rpc-mappings.py can parse it.
To void breaking test/lint/check-rpc-mappings.py script by running
clang-format, RPC command definitions should be disabled for clang-format.
Currently, the READWRITE macro cannot be passed any non-const temporaries, as
the SerReadWrite function only accepts lvalue references.
Deserializing into a temporary is very common, however. See for example
things like 's >> VARINT(n)'. The VARINT macro produces a temporary wrapper
that holds a reference to n.
Fix this by accepting non-const rvalue references instead of lvalue references.
We don't propagate the rvalue-ness down, as there are no useful optimizations
that only apply to temporaries.
Then use this new functionality to get rid of many (but not all) uses of the
'REF' macro (which casts away constness).
Use C++11's better capability of expressing an interface of a non-copyable class by publicly deleting its copy ctor and assignment operator instead of just declaring them private.
176c021 [qa] Test non-atomic chainstate writes (Suhas Daftuar)
d6af06d Dont create pcoinsTip until after ReplayBlocks. (Matt Corallo)
eaca1b7 Random db flush crash simulator (Pieter Wuille)
0580ee0 Adapt memory usage estimation for flushing (Pieter Wuille)
013a56a Non-atomic flushing using the blockchain as replay journal (Pieter Wuille)
b3a279c [MOVEONLY] Move LastCommonAncestor to chain (Pieter Wuille)
Tree-SHA512: 47ccc62303f9075c44d2a914be75bd6969ff881a857a2ff1227f05ec7def6f4c71c46680c5a28cb150c814999526797dc05cf2701fde1369c06169f46eccddee
This removes the possibility for GetCoin/HaveCoin/HaveCoinInCache to return
true while the respective coin is spent. By doing it across all calls, some
extra checks can be eliminated.
coins_tests is modified to call HaveCoin sometimes before and sometimes
after AccessCoin. A further change is needed because the semantics for
GetCoin slightly changed, causing a pruned entry in the parent cache to not
be pulled into the child in FetchCoin.
9417d7a33 Be much more agressive in AccessCoin docs. (Matt Corallo)
f58349ca8 Restore some assert semantics in sigop cost calculations (Matt Corallo)
3533fb4d3 Return a bool in SpendCoin to restore pre-per-utxo assert semantics (Matt Corallo)
ec1271f2b Remove useless mapNextTx lookup in CTxMemPool::TrimToSize. (Matt Corallo)
Tree-SHA512: 158a4bce063eac93e1d50709500a10a7cb1fb3271f10ed445d701852fce713e2bf0da3456088e530ab005f194ef4a2adf0c7cb23226b160cecb37a79561f29ca
3ff1fa8 Use override keyword on CCoinsView overrides (Russell Yanofsky)
24e44c3 Don't return stale data from CCoinsViewCache::Cursor() (Russell Yanofsky)
Tree-SHA512: 08699dae0925ffb9c018f02612ac6b7eaf73ec331e2f4f934f1fe25a2ce120735fa38596926e924897c203f7470e99f0a99cf70d2ce31ff428b105e16583a861
While the current implementation is pretty free, there is a lot
of possibility for this to blow up in our face with future changes,
especially as the backing map gets tweaked.
CCoinsViewCache doesn't actually support cursor iteration returning the
current contents of the cache, so raise an error when the cursor method is
called instead of returning a cursor that iterates over stale data.
Also update the gettxoutsetinfo RPC which was relying on the old behavior to be
explicit about which view it is returning data about.
This patch makes several related changes:
* Changes the CCoinsView virtual methods (GetCoins, HaveCoins, ...)
to be COutPoint/Coin-based rather than txid/CCoins-based.
* Changes the chainstate db to a new incompatible format that is also
COutPoint/Coin based.
* Implements reconstruction code for hash_serialized_2.
* Adapts the coins_tests unit tests (thanks to Russell Yanofsky).
A side effect of the new CCoinsView model is that we can no longer
use the (unreliable) test for transaction outputs in the UTXO set
to determine whether we already have a particular transaction.
James O'Beirne