GlcoinCore/elements
1
0
Fork 0
mirror of https://github.com/ElementsProject/elements.git synced 2026-08-17 13:07:54 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

Fix elements multiple-header-download issue.

Browse source 
This fixes an issue which causes Elements to download the blockchain headers
multiple times during initial block download.

In particular: each time we receive an INV P2P message with a new block
(about once a minute), we start downloading the headers, again, in parallel
with any existing download(s) in progress.

With this change, after we receive each batch of headers, we check whether
any of the headers in it were new to us. If not (they were all duplicates),
we stop there, and do not ask the peer for another batch. This reduces the
maximum amount of duplication to about 2x, which is not ideal, but a HUGE
improvement.
This commit is contained in:
Glenn Willen 2021-11-09 21:06:42 -08:00
parent 04cedf3f6b
commit cdfb4c9c6c
3 changed files with 23 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

6
src/net_processing.cpp
View file

@ -1843,7 +1843,8 @@ void PeerManager::ProcessHeadersMessage(CNode& pfrom, const std::vector<CBlockHe
}
BlockValidationState state;
if (!m_chainman.ProcessNewBlockHeaders(headers, state, m_chainparams, &pindexLast)) {
bool all_duplicate = false;
if (!m_chainman.ProcessNewBlockHeaders(headers, state, m_chainparams, &pindexLast, &all_duplicate)) {
if (state.IsInvalid()) {
MaybePunishNodeForBlock(pfrom.GetId(), state, via_compact_block, "invalid header received");
return;
@ -1869,10 +1870,11 @@ void PeerManager::ProcessHeadersMessage(CNode& pfrom, const std::vector<CBlockHe
nodestate->m_last_block_announcement = GetTime();
}
if (nCount == MAX_HEADERS_RESULTS) {
if (nCount == MAX_HEADERS_RESULTS && !all_duplicate) {
// Headers message had its maximum size; the peer may have more headers.
// TODO: optimize: if pindexLast is an ancestor of ::ChainActive().Tip or pindexBestHeader, continue
// from there instead.
// HOWEVER, if all headers we got this time were duplicates that we already had, don't ask for any more.
LogPrint(BCLog::NET, "more getheaders (%d) to end to peer=%d (startheight:%d)\n", pindexLast->nHeight, pfrom.GetId(), pfrom.nStartingHeight);
m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETHEADERS, ::ChainActive().GetLocator(pindexLast), uint256()));
}

19
src/validation.cpp
View file

@ -4036,16 +4036,22 @@ static bool ContextualCheckBlock(const CBlock& block, BlockValidationState& stat
return true;
}
bool BlockManager::AcceptBlockHeader(const CBlockHeader& block, BlockValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex)
bool BlockManager::AcceptBlockHeader(const CBlockHeader& block, BlockValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex, bool* duplicate)
{
AssertLockHeld(cs_main);
// Check for duplicate
uint256 hash = block.GetHash();
BlockMap::iterator miSelf = m_block_index.find(hash);
CBlockIndex *pindex = nullptr;
if (duplicate) {
*duplicate = false;
}
if (hash != chainparams.GetConsensus().hashGenesisBlock) {
if (miSelf != m_block_index.end()) {
// Block header is already known.
if (duplicate) {
*duplicate = true;
}
pindex = miSelf->second;
if (ppindex)
*ppindex = pindex;
@ -4125,17 +4131,24 @@ bool BlockManager::AcceptBlockHeader(const CBlockHeader& block, BlockValidationS
}
// Exposed wrapper for AcceptBlockHeader
bool ChainstateManager::ProcessNewBlockHeaders(const std::vector<CBlockHeader>& headers, BlockValidationState& state, const CChainParams& chainparams, const CBlockIndex** ppindex)
bool ChainstateManager::ProcessNewBlockHeaders(const std::vector<CBlockHeader>& headers, BlockValidationState& state, const CChainParams& chainparams, const CBlockIndex** ppindex, bool* all_duplicate)
{
AssertLockNotHeld(cs_main);
{
LOCK(cs_main);
if (all_duplicate) {
*all_duplicate = true;
}
bool duplicate = false;
for (const CBlockHeader& header : headers) {
CBlockIndex *pindex = nullptr; // Use a temp pindex instead of ppindex to avoid a const_cast
bool accepted = m_blockman.AcceptBlockHeader(
header, state, chainparams, &pindex);
header, state, chainparams, &pindex, &duplicate);
::ChainstateActive().CheckBlockIndex(chainparams.GetConsensus());
if (all_duplicate) {
(*all_duplicate) &= duplicate; // False if any are false
}
if (!accepted) {
return false;
}

5
src/validation.h
View file

@ -440,7 +440,8 @@ public:
const CBlockHeader& block,
BlockValidationState& state,
const CChainParams& chainparams,
CBlockIndex** ppindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
CBlockIndex** ppindex,
bool* duplicate = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
~BlockManager() {
Unload();
@ -926,7 +927,7 @@ public:
* @param[in] chainparams The params for the chain we want to connect to
* @param[out] ppindex If set, the pointer will be set to point to the last new block index object for the given headers
*/
bool ProcessNewBlockHeaders(const std::vector<CBlockHeader>& block, BlockValidationState& state, const CChainParams& chainparams, const CBlockIndex** ppindex = nullptr) LOCKS_EXCLUDED(cs_main);
bool ProcessNewBlockHeaders(const std::vector<CBlockHeader>& block, BlockValidationState& state, const CChainParams& chainparams, const CBlockIndex** ppindex = nullptr, bool* all_duplicate = nullptr) LOCKS_EXCLUDED(cs_main);
//! Load the block tree and coins database from disk, initializing state if we're running with -reindex
bool LoadBlockIndex(const CChainParams& chainparams) EXCLUSIVE_LOCKS_REQUIRED(cs_main);