@Override
public void setReplicaContext(ReplicaContext replicaContext) {
this.config = replicaContext.getStaticConfiguration();
if (log == null) {
globalCheckpointPeriod = config.getGlobalCheckpointPeriod();
replicaCkpIndex = getCheckpointPortionIndex();
checkpointPortion = globalCheckpointPeriod / config.getN();
// byte[] state = getSnapshot();
if (config.isToLog()) {
int replicaId = config.getProcessId();
boolean isToLog = config.isToLog();
boolean syncLog = config.isToWriteSyncLog();
boolean syncCkp = config.isToWriteSyncCkp();
// log = new DurableStateLog(replicaId, state, computeHash(state), isToLog, syncLog,
// syncCkp);
log = new DurableStateLog(replicaId, null, null, isToLog, syncLog, syncCkp);
CSTState storedState = log.loadDurableState();
if (storedState.getLastCID() > -1) {
System.out.println("LAST CID RECOVERED FROM LOG: " + storedState.getLastCID());
setState(storedState);
getStateManager().setLastCID(storedState.getLastCID());
} else {
System.out.println("REPLICA IS IN INITIAL STATE");
}
}
getStateManager().askCurrentConsensusId();
}
}
/**
* Iterates over the commands to find if any replica took a checkpoint. When a replica take a
* checkpoint, it is necessary to save in an auxiliary table the position in the log in which that
* replica took the checkpoint. It is used during state transfer to find lower or upper log
* portions to be restored in the recovering replica. This iteration over commands is needed due
* to the batch execution strategy introduced with the durable techniques to improve state
* management. As several consensus instances can be executed in the same batch of commands, it is
* necessary to identify if the batch contains checkpoint indexes.
*
* @param msgCtxs the contexts of the consensus where the messages where executed. There is one
* msgCtx message for each command to be executed
* @return the index in which a replica is supposed to take a checkpoint. If there is no replica
* taking a checkpoint during the period comprised by this command batch, it is returned -1
*/
private int findCheckpointPosition(int[] cids) {
if (config.getGlobalCheckpointPeriod() < 1) return -1;
if (cids.length == 0) throw new IllegalArgumentException();
int firstCID = cids[0];
if ((firstCID + 1) % checkpointPortion == 0) {
return cidPosition(cids, firstCID);
} else {
int nextCkpIndex = (((firstCID / checkpointPortion) + 1) * checkpointPortion) - 1;
if (nextCkpIndex <= cids[cids.length - 1]) {
return cidPosition(cids, nextCkpIndex);
}
}
return -1;
}
/**
* Write commands to log file
*
* @param commands array of commands. Each command is an array of bytes
* @param msgCtx
*/
private void saveCommands(byte[][] commands, MessageContext[] msgCtx) {
if (!config.isToLog()) return;
if (commands.length != msgCtx.length) {
System.out.println("----SIZE OF COMMANDS AND MESSAGE CONTEXTS IS DIFFERENT----");
System.out.println(
"----COMMANDS: " + commands.length + ", CONTEXTS: " + msgCtx.length + " ----");
}
logLock.lock();
int cid = msgCtx[0].getConsensusId();
int batchStart = 0;
for (int i = 0; i <= msgCtx.length; i++) {
if (i
== msgCtx
.length) { // the batch command contains only one command or it is the last position
// of the array
byte[][] batch = Arrays.copyOfRange(commands, batchStart, i);
MessageContext[] batchMsgCtx = Arrays.copyOfRange(msgCtx, batchStart, i);
log.addMessageBatch(batch, batchMsgCtx, cid);
log.setLastCID(cid, globalCheckpointPeriod, checkpointPortion);
// if(batchStart > 0)
// System.out.println("Last batch: " + commands.length + "," + batchStart + "-" + i +
// "," + batch.length);
} else {
if (msgCtx[i].getConsensusId()
> cid) { // saves commands when the CID changes or when it is the last batch
byte[][] batch = Arrays.copyOfRange(commands, batchStart, i);
MessageContext[] batchMsgCtx = Arrays.copyOfRange(msgCtx, batchStart, i);
// System.out.println("THERE IS MORE THAN ONE CID in this batch." + commands.length +
// "," + batchStart + "-" + i + "," + batch.length);
log.addMessageBatch(batch, batchMsgCtx, cid);
log.setLastCID(cid, globalCheckpointPeriod, checkpointPortion);
cid = msgCtx[i].getConsensusId();
batchStart = i;
}
}
}
logLock.unlock();
}
private int getCheckpointPortionIndex() {
int numberOfReplicas = config.getN();
int ckpIndex = ((globalCheckpointPeriod / numberOfReplicas) * (config.getProcessId() + 1)) - 1;
return ckpIndex;
}