void Controller::checkMigration(Key& key, const Choice& current,
bool extraGet, shared_ptr<Value> valueGot) {
Requirements requirements;
size_t size;
{
lock_guard<mutex> guard(infoLock);
if (info.count(key) == 0) return;
requirements = *info[key].requirements.get();
size = info[key].size;
}
Condition condition = prepareCondition(key, size, requirements);
double estimatedCost;
Choice* choice = decider->findBetter(condition, current, extraGet,
&estimatedCost);
if (choice != nullptr) {
Dbg() << "migrating from " << current.desc() << " to " << choice->desc() << endl;
shared_ptr<Value> value;
Requirements migrateRequirements;
if (extraGet) {
value = current.getActor()->get(key, current.getProfile());
} else {
value = valueGot;
}
storeInto(key, value, *choice, requirements);
choice_id old_id = memory->remember(key, choice->getId());
deleteFrom(key, current);
accountant->recordMigrate(current.getId(), choice->getId(), size,
extraGet);
}
}
shared_ptr<Value> Controller::handleGet(Key& key, const Requirements& requirements) {
shared_ptr<Value> value;
Requirements mutable_requirements = requirements;
choice_id cid;
if (memory->recall(key, &cid)) {
auto cit = choices.find(cid);
assert(cit != choices.end());
Choice choice = cit->second;
accountant->recordGet(cid);
Actor* actor = choice.getActor();
Dbg() << "choice " << choice.desc() << "handle this" << endl;
if (requirements.prefer_url) {
value = actor->get_url(key, requirements.expiration, choice.getProfile());
}
if (!value) {
value = actor->get(key, choice.getProfile(), requirements.range, &mutable_requirements.metadata);
}
if (!value) {
Err() << "cannot find " << key.toString() << " in choice " << choice.desc() << endl;
for (auto& choice_pair : choices) {
Choice& choice = choice_pair.second;
if (choice.getActor()->get(key, choice.getProfile(), requirements.range, &mutable_requirements.metadata)) {
Err() << "found key in " << choice.desc() << "instead" << endl;
abort();
}
}
}
if (enableGetMigration) {
bool extraGet = !value->hasUrl();
checkMigration(key, choice, extraGet, value);
}
}
estimator->notifyGet(key, mutable_requirements);
if (enableStat) {
stat->notifyGet(key);
}
return value;
}
void Controller::storeInto(Key& key, shared_ptr<Value> value,
const Choice& choice, const Requirements& requirements) {
Actor* actor = choice.getActor();
Dbg() << "chose " << choice.desc() << " for this" << endl;
if (requirements.metadata.empty()) {
actor->put(key, value, choice.getProfile());
} else {
actor->put(key, value, choice.getProfile(), &requirements.metadata);
}
}
void Controller::deleteFrom(Key& key, const Choice& choice) {
Actor* actor = choice.getActor();
actor->del(key, choice.getProfile());
}
