Method getLatestCommitVersions

fdbclient/NativeAPI.actor.cpp:228–291

}

void DatabaseContext::getLatestCommitVersions(const Reference<LocationInfo>& locationInfo,
                                              Version readVersion,
                                              Reference<TransactionState> info,
                                              VersionVector& latestCommitVersions) {
	latestCommitVersions.clear();

	if (info->debugID.present()) {
		g_traceBatch.addEvent("TransactionDebug", info->debugID.get().first(), "NativeAPI.getLatestCommitVersions");
	}

	if (!info->readVersionObtainedFromGrvProxy) {
		return;
	}

	if (ssVersionVectorCache.getMaxVersion() == invalidVersion) {
		return;
	}

	if (readVersion > ssVersionVectorCache.getMaxVersion()) {
		if (!CLIENT_KNOBS->FORCE_GRV_CACHE_OFF && !info->options.skipGrvCache && info->options.useGrvCache) {
			return;
		} else {
			TraceEvent(SevError, "GetLatestCommitVersions")
			    .detail("ReadVersion", readVersion)
			    .detail("VersionVector", ssVersionVectorCache.toString());
			ASSERT(false);
		}
	}

	std::map<Version, std::set<Tag>> versionMap; // order the versions to be returned
	for (int i = 0; i < locationInfo->locations()->size(); i++) {
		bool updatedVersionMap = false;
		Version commitVersion = invalidVersion;
		Tag tag = invalidTag;
		auto iter = ssidTagMapping.find(locationInfo->locations()->getId(i));
		if (iter != ssidTagMapping.end()) {
			tag = iter->second;
			if (ssVersionVectorCache.hasVersion(tag)) {
				commitVersion = ssVersionVectorCache.getVersion(tag); // latest commit version
				if (commitVersion < readVersion) {
					updatedVersionMap = true;
					versionMap[commitVersion].insert(tag);
				}
			}
		}
		// commitVersion == readVersion is common, do not log.
		if (!updatedVersionMap && commitVersion != readVersion) {
			TraceEvent(SevDebug, "CommitVersionNotFoundForSS")
			    .detail("InSSIDMap", iter != ssidTagMapping.end() ? 1 : 0)
			    .detail("Tag", tag)
			    .detail("CommitVersion", commitVersion)
			    .detail("ReadVersion", readVersion)
			    .detail("VersionVector", ssVersionVectorCache.toString())
			    .setMaxEventLength(11000)
			    .setMaxFieldLength(10000);
			++transactionCommitVersionNotFoundForSS;
		}
	}