969c840db52da796c319f84c9a9a20b1de902ccf log,blocks: avoid `ComputeTotalSize` and `GetHash` work when logging is disabled (Lőrinc)
babfda332b6aa41143eb694193358ef2c76ebefe log,net: avoid `ComputeTotalSize` when logging is disabled (Lőrinc)
1658b8f82b99f9ba3b42a50ba1f72b19a38c8e75 refactor: rename `CTransaction::GetTotalSize` to signal that it's not cached (Lőrinc)
Pull request description:
### Context
The new accounting options introduced in https://github.com/bitcoin/bitcoin/pull/32582 can be quite heavy, and are not needed when debug logging is disabled.
### Problem
`PartiallyDownloadedBlock::FillBlock()` and `PeerManagerImpl::SendBlockTransactions()` accumulate transaction sizes for debug logging by calling `ComputeTotalSize()` in loops, which invokes expensive `GetSerializeSize()` serializations.
The block header hash is also only computed for the debug log.
### Fixes
Guard the size and hash calculations with `LogAcceptCategory()` checks so the serialization and hashing work only occurs when compact block debug logging is enabled.
Also modernized the surrounding code a bit since the change is quite trivial.
### Reproducer
You can test the change by starting an up-to-date `bitcoind` node with `-debug=cmpctblock` and observing compact block log lines such as:
> [cmpctblock] Successfully reconstructed block 00000000000000000001061eaa6c0fe79258e7f79606e67ac495765cb121a520 with 1 txn prefilled, 3122 txn from mempool (incl at least 3 from extra pool) and 641 txn (352126 bytes) requested
<details>
<summary>Test patch</summary>
```patch
diff --git a/src/blockencodings.cpp b/src/blockencodings.cpp
index 58620c93cc..f16eb38fa5 100644
--- a/src/blockencodings.cpp
+++ b/src/blockencodings.cpp
@@ -186,6 +186,7 @@ bool PartiallyDownloadedBlock::IsTxAvailable(size_t index) const
ReadStatus PartiallyDownloadedBlock::FillBlock(CBlock& block, const std::vector<CTransactionRef>& vtx_missing, bool segwit_active)
{
+ LogInfo("PartiallyDownloadedBlock::FillBlock called");
if (header.IsNull()) return READ_STATUS_INVALID;
block = header;
@@ -218,6 +219,7 @@ ReadStatus PartiallyDownloadedBlock::FillBlock(CBlock& block, const std::vector<
}
if (LogAcceptCategory(BCLog::CMPCTBLOCK, BCLog::Level::Debug)) {
+ LogInfo("debug log enabled");
const uint256 hash{block.GetHash()}; // avoid cleared header
uint32_t tx_missing_size{0};
for (const auto& tx : vtx_missing) tx_missing_size += tx->ComputeTotalSize(); // avoid cleared txn_available
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 5600c8d389..c081825f77 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -2470,6 +2470,7 @@ uint32_t PeerManagerImpl::GetFetchFlags(const Peer& peer) const
void PeerManagerImpl::SendBlockTransactions(CNode& pfrom, Peer& peer, const CBlock& block, const BlockTransactionsRequest& req)
{
+ LogInfo("PeerManagerImpl::SendBlockTransactions called");
BlockTransactions resp(req);
for (size_t i = 0; i < req.indexes.size(); i++) {
if (req.indexes[i] >= block.vtx.size()) {
@@ -2480,6 +2481,7 @@ void PeerManagerImpl::SendBlockTransactions(CNode& pfrom, Peer& peer, const CBlo
}
if (LogAcceptCategory(BCLog::CMPCTBLOCK, BCLog::Level::Debug)) {
+ LogInfo("debug log enabled");
uint32_t tx_requested_size{0};
for (const auto i : req.indexes) tx_requested_size += block.vtx[i]->ComputeTotalSize();
LogDebug(BCLog::CMPCTBLOCK, "Peer %d sent us a GETBLOCKTXN for block %s, sending a BLOCKTXN with %u txns. (%u bytes)\n", pfrom.GetId(), block.GetHash().ToString(), resp.txn.size(), tx_requested_size);
```
</details>
ACKs for top commit:
davidgumberg:
reACK 969c840db5
achow101:
ACK 969c840db52da796c319f84c9a9a20b1de902ccf
hodlinator:
re-ACK 969c840db52da796c319f84c9a9a20b1de902ccf
sedited:
Re-ACK 969c840db52da796c319f84c9a9a20b1de902ccf
danielabrozzoni:
reACK 969c840db52da796c319f84c9a9a20b1de902ccf
Tree-SHA512: 9780102d29778165144e3602d934ed4cb96660fd7b9ff2581b223c619e419139b8348e60f226af448702ae527736a1806d169b44342c5a82795590f664e16efe
d938947b3a89a61784a72c533df623f9eb2fec49 doc: Add "Using IWYU" to Developer Notes (Hennadii Stepanov)
e1a90bcecc823a4abaa2a57f393cad675a2ccbc0 iwyu: Do not export `crypto/hex_base.h` header (Hennadii Stepanov)
19a2edde50c38412712306bf527faad6cbf81c2c iwyu: Do not export C++ headers in most cases (Hennadii Stepanov)
Pull request description:
First two commits address comments from discussion in https://github.com/bitcoin/bitcoin/pull/33779:
- https://github.com/bitcoin/bitcoin/pull/33779#discussion_r2697579248
- https://github.com/bitcoin/bitcoin/pull/33779#discussion_r2697707343
The last commit adds a new section to the Developer Notes to document IWYU usage.
ACKs for top commit:
maflcko:
re-ACK d938947b3a89a61784a72c533df623f9eb2fec49 🚀
Tree-SHA512: 8d6c63e9d2fd190815211d80e654cb7379d16b6611b8851444f49bbbaa0fbc93557675fbcc558afd9a1cdf643570fba5eff9c1aecb5530f978797387b10b9a11
Transaction hashes are cached, it may not be intuitive that their sizes are actually recalculated every time.
This is done before the other refactors to clarify why we want to avoid calling this method;
Co-authored-by: maflcko <6399679+maflcko@users.noreply.github.com>
