Merge #13151: net: Serve blocks directly from disk when possible

0bf431870e net: Serve blocks directly from disk when possible (Wladimir J. van der Laan)

Pull request description:

  In `ProcessGetBlockData`, send the block data directly from disk if type MSG_WITNESS_BLOCK is requested. This is a valid shortcut as the on-disk format matches the network format.

  This is expected to increase performance because a deserialization and subsequent serialization roundtrip is avoided.

Tree-SHA512: 9a9500b4c1354eaae1a6f1c6ef2416c1c1985029852589266f3a70e808f6c7482c135e9ab251a527566935378ab7c32dba4ed43ba5451e802d8e72b77d1ba472
This commit is contained in:
Wladimir J. van der Laan
2018-05-23 19:31:38 +02:00
3 changed files with 107 additions and 47 deletions

View File

@@ -1137,6 +1137,52 @@ bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex, const Consensus
return true;
}
bool ReadRawBlockFromDisk(std::vector<uint8_t>& block, const CDiskBlockPos& pos, const CMessageHeader::MessageStartChars& message_start)
{
CDiskBlockPos hpos = pos;
hpos.nPos -= 8; // Seek back 8 bytes for meta header
CAutoFile filein(OpenBlockFile(hpos, true), SER_DISK, CLIENT_VERSION);
if (filein.IsNull()) {
return error("%s: OpenBlockFile failed for %s", __func__, pos.ToString());
}
try {
CMessageHeader::MessageStartChars blk_start;
unsigned int blk_size;
filein >> blk_start >> blk_size;
if (memcmp(blk_start, message_start, CMessageHeader::MESSAGE_START_SIZE)) {
return error("%s: Block magic mismatch for %s: %s versus expected %s", __func__, pos.ToString(),
HexStr(blk_start, blk_start + CMessageHeader::MESSAGE_START_SIZE),
HexStr(message_start, message_start + CMessageHeader::MESSAGE_START_SIZE));
}
if (blk_size > MAX_SIZE) {
return error("%s: Block data is larger than maximum deserialization size for %s: %s versus %s", __func__, pos.ToString(),
blk_size, MAX_SIZE);
}
block.resize(blk_size); // Zeroing of memory is intentional here
filein.read((char*)block.data(), blk_size);
} catch(const std::exception& e) {
return error("%s: Read from block file failed: %s for %s", __func__, e.what(), pos.ToString());
}
return true;
}
bool ReadRawBlockFromDisk(std::vector<uint8_t>& block, const CBlockIndex* pindex, const CMessageHeader::MessageStartChars& message_start)
{
CDiskBlockPos block_pos;
{
LOCK(cs_main);
block_pos = pindex->GetBlockPos();
}
return ReadRawBlockFromDisk(block, block_pos, message_start);
}
CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams)
{
int halvings = nHeight / consensusParams.nSubsidyHalvingInterval;