/** Called by RequestStarter to find a request to run. */
@Override
public ChosenBlock grabRequest() {
boolean needsRefill = true;
while (true) {
PersistentChosenRequest reqGroup = null;
synchronized (starterQueue) {
short bestPriority = Short.MAX_VALUE;
for (PersistentChosenRequest req : starterQueue) {
if (req.prio == RequestStarter.MINIMUM_PRIORITY_CLASS) {
if (logDEBUG)
Logger.debug(
this, "Ignoring paused persistent request: " + req + " prio: " + req.prio);
continue; // Ignore paused requests
}
if (req.prio < bestPriority) {
bestPriority = req.prio;
reqGroup = req;
}
}
}
if (reqGroup != null) {
// Try to find a better non-persistent request
if (logMINOR)
Logger.minor(this, "Persistent request: " + reqGroup + " prio " + reqGroup.prio);
ChosenBlock better = getBetterNonPersistentRequest(reqGroup.prio);
if (better != null) {
if (better.getPriority() > reqGroup.prio) {
Logger.error(
this, "Selected " + better + " as better than " + reqGroup + " but isn't better!");
}
if (logMINOR) Logger.minor(this, "Returning better: " + better);
return better;
}
}
if (reqGroup == null) {
queueFillRequestStarterQueue();
return getBetterNonPersistentRequest(Short.MAX_VALUE);
}
ChosenBlock block;
synchronized (starterQueue) {
block = reqGroup.grabNotStarted(clientContext.fastWeakRandom, this);
if (block == null) {
if (logMINOR) Logger.minor(this, "No block found on " + reqGroup);
int finalLength = 0;
for (int i = 0; i < starterQueue.size(); i++) {
if (starterQueue.get(i) == reqGroup) {
starterQueue.remove(i);
if (logMINOR)
Logger.minor(this, "Removed " + reqGroup + " from starter queue because is empty");
i--;
} else {
finalLength += starterQueue.get(i).sizeNotStarted();
}
}
needsRefill = finalLength < MAX_STARTER_QUEUE_SIZE;
continue;
} else {
// Prevent this request being selected, even though we may remove the PCR from the starter
// queue
// in the very near future. When the PCR finishes, the requests will be un-blocked.
if (!runningPersistentRequests.contains(reqGroup.request))
runningPersistentRequests.add(reqGroup.request);
}
}
if (needsRefill) queueFillRequestStarterQueue();
if (logMINOR) Logger.minor(this, "grabRequest() returning " + block + " for " + reqGroup);
return block;
}
}
