Function commitMessages

fdbserver/OldTLogServer_6_2.actor.cpp:1245–1349

}

void commitMessages(TLogData* self,
                    Reference<LogData> logData,
                    Version version,
                    const std::vector<TagsAndMessage>& taggedMessages) {
	// SOMEDAY: This method of copying messages is reasonably memory efficient, but it's still a lot of bytes copied.
	// Find a way to do the memory allocation right as we receive the messages in the network layer.

	int64_t addedBytes = 0;
	int64_t overheadBytes = 0;
	int expectedBytes = 0;
	int txsBytes = 0;

	if (!taggedMessages.size()) {
		return;
	}

	int msgSize = 0;
	for (auto& i : taggedMessages) {
		msgSize += i.message.size();
	}

	// Grab the last block in the blocks list so we can share its arena
	// We pop all of the elements of it to create a "fresh" vector that starts at the end of the previous vector
	Standalone<VectorRef<uint8_t>> block;
	if (logData->messageBlocks.empty()) {
		block = Standalone<VectorRef<uint8_t>>();
		block.reserve(block.arena(), std::max<int64_t>(SERVER_KNOBS->TLOG_MESSAGE_BLOCK_BYTES, msgSize));
	} else {
		block = logData->messageBlocks.back().second;
	}

	block.pop_front(block.size());

	for (auto& msg : taggedMessages) {
		if (msg.message.size() > block.capacity() - block.size()) {
			logData->messageBlocks.emplace_back(version, block);
			addedBytes += int64_t(block.size()) * SERVER_KNOBS->TLOG_MESSAGE_BLOCK_OVERHEAD_FACTOR;
			block = Standalone<VectorRef<uint8_t>>();
			block.reserve(block.arena(), std::max<int64_t>(SERVER_KNOBS->TLOG_MESSAGE_BLOCK_BYTES, msgSize));
		}

		block.append(block.arena(), msg.message.begin(), msg.message.size());
		for (auto tag : msg.tags) {
			if (logData->locality == tagLocalitySatellite) {
				if (!(tag.locality == tagLocalityTxs || tag.locality == tagLocalityLogRouter || tag == txsTag)) {
					continue;
				}
			} else if (!(logData->locality == tagLocalitySpecial || logData->locality == tag.locality ||
			             tag.locality < 0)) {
				continue;
			}

			if (tag.locality == tagLocalityLogRouter) {
				if (!logData->logRouterTags) {
					continue;
				}
				tag.id = tag.id % logData->logRouterTags;
			}