bool QueryManager::fetchNormalWorkOrders(const dag_node_index index) {
bool generated_new_workorders = false;
if (!query_exec_state_->hasDoneGenerationWorkOrders(index)) {
// Do not fetch any work units until all blocking dependencies are met.
// The releational operator is not aware of blocking dependencies for
// uncorrelated scalar queries.
if (!checkAllBlockingDependenciesMet(index)) {
return false;
}
const size_t num_pending_workorders_before =
workorders_container_->getNumNormalWorkOrders(index);
const bool done_generation =
query_dag_->getNodePayloadMutable(index)->getAllWorkOrders(workorders_container_.get(),
query_context_.get(),
storage_manager_,
foreman_client_id_,
bus_);
if (done_generation) {
query_exec_state_->setDoneGenerationWorkOrders(index);
}
// TODO(shoban): It would be a good check to see if operator is making
// useful progress, i.e., the operator either generates work orders to
// execute or still has pending work orders executing. However, this will not
// work if Foreman polls operators without feeding data. This check can be
// enabled, if Foreman is refactored to call getAllWorkOrders() only when
// pending work orders are completed or new input blocks feed.
generated_new_workorders =
(num_pending_workorders_before <
workorders_container_->getNumNormalWorkOrders(index));
}
return generated_new_workorders;
}
void QueryManagerBase::markOperatorFinished(const dag_node_index index) {
query_exec_state_->setExecutionFinished(index);
for (const dag_node_index dependent_op_index : blocking_dependents_[index]) {
blocking_dependencies_[dependent_op_index].erase(index);
}
for (const dag_node_index dependent_op_index : output_consumers_[index]) {
non_blocking_dependencies_[dependent_op_index].erase(index);
}
RelationalOperator *op = query_dag_->getNodePayloadMutable(index);
op->updateCatalogOnCompletion();
const relation_id output_rel = op->getOutputRelationID();
for (const pair<dag_node_index, bool> &dependent_link : query_dag_->getDependents(index)) {
const dag_node_index dependent_op_index = dependent_link.first;
if (output_rel >= 0) {
// Signal dependent operator that current operator is done feeding input blocks.
query_dag_->getNodePayloadMutable(dependent_op_index)->doneFeedingInputBlocks(output_rel);
}
if (checkAllBlockingDependenciesMet(dependent_op_index)) {
// Process the dependent operator (of the operator whose WorkOrder
// was just executed) for which all the dependencies have been met.
if (!fetchNormalWorkOrders(dependent_op_index) &&
non_blocking_dependencies_[dependent_op_index].empty() &&
checkNormalExecutionOver(dependent_op_index) &&
(!checkRebuildRequired(dependent_op_index) || initiateRebuild(dependent_op_index))) {
markOperatorFinished(dependent_op_index);
}
}
}
}
void Foreman::markOperatorFinished(dag_node_index index) {
execution_finished_[index] = true;
++num_operators_finished_;
const relation_id output_rel = query_dag_->getNodePayload(index).getOutputRelationID();
for (pair<dag_node_index, bool> dependent_link : query_dag_->getDependents(index)) {
RelationalOperator *dependent_op = query_dag_->getNodePayloadMutable(dependent_link.first);
// Signal dependent operator that current operator is done feeding input blocks.
if (output_rel >= 0) {
dependent_op->doneFeedingInputBlocks(output_rel);
}
if (checkAllBlockingDependenciesMet(dependent_link.first)) {
dependent_op->informAllBlockingDependenciesMet();
}
}
}
void QueryManager::processRebuildWorkOrderCompleteMessage(const dag_node_index op_index) {
query_exec_state_->decrementNumRebuildWorkOrders(op_index);
if (checkRebuildOver(op_index)) {
markOperatorFinished(op_index);
for (const pair<dag_node_index, bool> &dependent_link :
query_dag_->getDependents(op_index)) {
const dag_node_index dependent_op_index = dependent_link.first;
if (checkAllBlockingDependenciesMet(dependent_op_index)) {
processOperator(dependent_op_index, true);
}
}
}
}
void QueryManagerBase::processDataPipelineMessage(const dag_node_index op_index,
const block_id block,
const relation_id rel_id,
const partition_id part_id) {
for (const dag_node_index consumer_index :
output_consumers_[op_index]) {
// Feed the streamed block to the consumer. Note that 'output_consumers_'
// only contain those dependents of operator with index = op_index which are
// eligible to receive streamed input.
query_dag_->getNodePayloadMutable(consumer_index)->feedInputBlock(block, rel_id, part_id);
// Because of the streamed input just fed, check if there are any new
// WorkOrders available and if so, fetch them.
if (checkAllBlockingDependenciesMet(consumer_index)) {
fetchNormalWorkOrders(consumer_index);
}
}
}
void QueryManager::markOperatorFinished(const dag_node_index index) {
query_exec_state_->setExecutionFinished(index);
RelationalOperator *op = query_dag_->getNodePayloadMutable(index);
op->updateCatalogOnCompletion();
const relation_id output_rel = op->getOutputRelationID();
for (const pair<dag_node_index, bool> &dependent_link : query_dag_->getDependents(index)) {
const dag_node_index dependent_op_index = dependent_link.first;
RelationalOperator *dependent_op = query_dag_->getNodePayloadMutable(dependent_op_index);
// Signal dependent operator that current operator is done feeding input blocks.
if (output_rel >= 0) {
dependent_op->doneFeedingInputBlocks(output_rel);
}
if (checkAllBlockingDependenciesMet(dependent_op_index)) {
dependent_op->informAllBlockingDependenciesMet();
}
}
}
void Foreman::processOperator(RelationalOperator *op,
dag_node_index index,
bool recursively_check_dependents) {
if (fetchNormalWorkOrders(op, index)) {
// Fetched work orders. Return to wait for the generated work orders to
// execute, and skip the execution-finished checks.
return;
}
if (checkNormalExecutionOver(index)) {
if (checkRebuildRequired(index)) {
if (!checkRebuildInitiated(index)) {
// Rebuild hasn't started, initiate it.
if (initiateRebuild(index)) {
// Rebuild initiated and completed right away.
markOperatorFinished(index);
} else {
// Rebuild WorkOrders have been generated.
return;
}
} else if (checkRebuildOver(index)) {
// Rebuild had been initiated and it is over.
markOperatorFinished(index);
}
} else {
// Rebuild is not required and normal execution over, mark finished.
markOperatorFinished(index);
}
// If we reach here, that means the operator has been marked as finished.
if (recursively_check_dependents) {
for (pair<dag_node_index, bool> dependent_link :
query_dag_->getDependents(index)) {
if (checkAllBlockingDependenciesMet(dependent_link.first)) {
processOperator(
query_dag_->getNodePayloadMutable(dependent_link.first),
dependent_link.first, true);
}
}
}
}
}
void Foreman::initialize() {
if (cpu_id_ >= 0) {
// We can pin the foreman thread to a CPU if specified.
ThreadUtil::BindToCPU(cpu_id_);
}
DEBUG_ASSERT(query_dag_ != nullptr);
initializeState();
// Collect all the workorders from all the relational operators in the DAG.
const dag_node_index dag_size = query_dag_->size();
for (dag_node_index index = 0; index < dag_size; ++index) {
if (checkAllBlockingDependenciesMet(index)) {
query_dag_->getNodePayloadMutable(index)->informAllBlockingDependenciesMet();
processOperator(index, false);
}
}
// Dispatch the WorkOrders generated so far.
dispatchWorkerMessages(0, 0);
}
void QueryManager::processWorkOrderCompleteMessage(
const dag_node_index op_index) {
query_exec_state_->decrementNumQueuedWorkOrders(op_index);
// Check if new work orders are available and fetch them if so.
fetchNormalWorkOrders(op_index);
if (checkRebuildRequired(op_index)) {
if (checkNormalExecutionOver(op_index)) {
if (!checkRebuildInitiated(op_index)) {
if (initiateRebuild(op_index)) {
// Rebuild initiated and completed right away.
markOperatorFinished(op_index);
} else {
// Rebuild under progress.
}
} else if (checkRebuildOver(op_index)) {
// Rebuild was under progress and now it is over.
markOperatorFinished(op_index);
}
} else {
// Normal execution under progress for this operator.
}
} else if (checkOperatorExecutionOver(op_index)) {
// Rebuild not required for this operator and its normal execution is
// complete.
markOperatorFinished(op_index);
}
for (const pair<dag_node_index, bool> &dependent_link :
query_dag_->getDependents(op_index)) {
const dag_node_index dependent_op_index = dependent_link.first;
if (checkAllBlockingDependenciesMet(dependent_op_index)) {
// Process the dependent operator (of the operator whose WorkOrder
// was just executed) for which all the dependencies have been met.
processOperator(dependent_op_index, true);
}
}
}
// TODO(harshad) - There is duplication in terms of functionality provided by
// TMB and ForemanMessage class with respect to determining the message types.
// Try to use TMB message types for infering the messsage types consistently.
bool Foreman::processMessage(const ForemanMessage &message) {
const dag_node_index dag_size = query_dag_->size();
// Get the relational operator that caused this message to be sent.
dag_node_index response_op_index = message.getRelationalOpIndex();
const int worker_id = message.getWorkerID();
switch (message.getType()) {
case ForemanMessage::kWorkOrderCompletion:
{
// Completion of a regular WorkOrder.
DEBUG_ASSERT(worker_id >= 0);
--queued_workorders_per_op_[response_op_index];
// As the given worker finished executing a WorkOrder, decrement its
// number of queued WorkOrders.
workers_->decrementNumQueuedWorkOrders(worker_id);
// Check if new work orders are available and fetch them if so.
fetchNormalWorkOrders(
query_dag_->getNodePayloadMutable(response_op_index),
response_op_index);
if (checkRebuildRequired(response_op_index)) {
if (checkNormalExecutionOver(response_op_index)) {
if (!checkRebuildInitiated(response_op_index)) {
if (initiateRebuild(response_op_index)) {
// Rebuild initiated and completed right away.
markOperatorFinished(response_op_index);
} else {
// Rebuild under progress.
}
} else if (checkRebuildOver(response_op_index)) {
// Rebuild was under progress and now it is over.
markOperatorFinished(response_op_index);
}
} else {
// Normal execution under progress for this operator.
}
} else if (checkOperatorExecutionOver(response_op_index)) {
// Rebuild not required for this operator and its normal execution is
// complete.
markOperatorFinished(response_op_index);
}
for (pair<dag_node_index, bool> dependent_link :
query_dag_->getDependents(response_op_index)) {
RelationalOperator *dependent_op =
query_dag_->getNodePayloadMutable(dependent_link.first);
if (checkAllBlockingDependenciesMet(dependent_link.first)) {
// Process the dependent operator (of the operator whose WorkOrder
// was just executed) for which all the dependencies have been met.
processOperator(dependent_op, dependent_link.first, true);
}
}
}
break;
case ForemanMessage::kRebuildCompletion:
{
DEBUG_ASSERT(worker_id >= 0);
// Completion of a rebuild WorkOrder.
--rebuild_status_[response_op_index].second;
workers_->decrementNumQueuedWorkOrders(worker_id);
if (checkRebuildOver(response_op_index)) {
markOperatorFinished(response_op_index);
for (pair<dag_node_index, bool> dependent_link :
query_dag_->getDependents(response_op_index)) {
RelationalOperator *dependent_op =
query_dag_->getNodePayloadMutable(dependent_link.first);
if (checkAllBlockingDependenciesMet(dependent_link.first)) {
processOperator(dependent_op, dependent_link.first, true);
}
}
}
}
break;
case ForemanMessage::kDataPipeline:
{
// Data streaming message. Possible senders of this message include
// InsertDestination and some operators which modify existing blocks.
for (dag_node_index consumer_index :
output_consumers_[response_op_index]) {
RelationalOperator *consumer_op =
query_dag_->getNodePayloadMutable(consumer_index);
// Feed the streamed block to the consumer. Note that
// output_consumers_ only contain those dependents of operator with
// index = response_op_index which are eligible to receive streamed
// input.
consumer_op->feedInputBlock(message.getOutputBlockID(),
message.getRelationID());
// Because of the streamed input just fed, check if there are any new
// WorkOrders available and if so, fetch them.
fetchNormalWorkOrders(consumer_op, consumer_index);
} // end for (feeding input to dependents)
}
break;
case ForemanMessage::kWorkOrdersAvailable: {
// Check if new work orders are available.
fetchNormalWorkOrders(
query_dag_->getNodePayloadMutable(response_op_index),
response_op_index);
break;
}
default:
FATAL_ERROR("Unknown ForemanMessage type");
}
// Dispatch the WorkerMessages to the workers. We prefer to start the search
// for the schedulable WorkOrders beginning from response_op_index. The first
// candidate worker to receive the next WorkOrder is the one that sent the
// response message to Foreman.
dispatchWorkerMessages(((worker_id >= 0) ? worker_id : 0), response_op_index);
return num_operators_finished_ == dag_size;
}
QueryManager::QueryManager(const tmb::client_id foreman_client_id,
const std::size_t num_numa_nodes,
QueryHandle *query_handle,
CatalogDatabaseLite *catalog_database,
StorageManager *storage_manager,
tmb::MessageBus *bus)
: foreman_client_id_(foreman_client_id),
query_id_(DCHECK_NOTNULL(query_handle)->query_id()),
catalog_database_(DCHECK_NOTNULL(catalog_database)),
storage_manager_(DCHECK_NOTNULL(storage_manager)),
bus_(DCHECK_NOTNULL(bus)) {
DCHECK(query_handle->getQueryPlanMutable() != nullptr);
query_dag_ = query_handle->getQueryPlanMutable()->getQueryPlanDAGMutable();
DCHECK(query_dag_ != nullptr);
const dag_node_index num_operators_in_dag = query_dag_->size();
output_consumers_.resize(num_operators_in_dag);
blocking_dependencies_.resize(num_operators_in_dag);
query_exec_state_.reset(new QueryExecutionState(num_operators_in_dag));
workorders_container_.reset(
new WorkOrdersContainer(num_operators_in_dag, num_numa_nodes));
query_context_.reset(new QueryContext(query_handle->getQueryContextProto(),
*catalog_database_,
storage_manager_,
foreman_client_id_,
bus_));
for (dag_node_index node_index = 0;
node_index < num_operators_in_dag;
++node_index) {
const QueryContext::insert_destination_id insert_destination_index =
query_dag_->getNodePayload(node_index).getInsertDestinationID();
if (insert_destination_index != QueryContext::kInvalidInsertDestinationId) {
// Rebuild is necessary whenever InsertDestination is present.
query_exec_state_->setRebuildRequired(node_index);
query_exec_state_->setRebuildStatus(node_index, 0, false);
}
for (const pair<dag_node_index, bool> &dependent_link :
query_dag_->getDependents(node_index)) {
const dag_node_index dependent_op_index = dependent_link.first;
if (!query_dag_->getLinkMetadata(node_index, dependent_op_index)) {
// The link is not a pipeline-breaker. Streaming of blocks is possible
// between these two operators.
output_consumers_[node_index].push_back(dependent_op_index);
} else {
// The link is a pipeline-breaker. Streaming of blocks is not possible
// between these two operators.
blocking_dependencies_[dependent_op_index].push_back(node_index);
}
}
}
// Collect all the workorders from all the relational operators in the DAG.
for (dag_node_index index = 0; index < num_operators_in_dag; ++index) {
if (checkAllBlockingDependenciesMet(index)) {
query_dag_->getNodePayloadMutable(index)->informAllBlockingDependenciesMet();
processOperator(index, false);
}
}
}
