Normal Projections analysis using query plan [In progress]

This commit is contained in:
Nikolai Kochetov 2023-02-13 19:56:31 +00:00
parent e6e486c4a1
commit 522a39f93f
3 changed files with 245 additions and 3 deletions

View File

@ -93,7 +93,8 @@ using Stack = std::vector<Frame>;
void optimizePrimaryKeyCondition(const Stack & stack);
void optimizeReadInOrder(QueryPlan::Node & node, QueryPlan::Nodes & nodes);
void optimizeAggregationInOrder(QueryPlan::Node & node, QueryPlan::Nodes &);
bool optimizeUseProjections(QueryPlan::Node & node, QueryPlan::Nodes &);
bool optimizeUseAggProjections(QueryPlan::Node & node, QueryPlan::Nodes & nodes);
bool optimizeUseNormalProjections(Stack & stack, QueryPlan::Nodes & nodes);
/// Enable memory bound merging of aggregation states for remote queries
/// in case it was enabled for local plan

View File

@ -122,7 +122,7 @@ void optimizeTreeSecondPass(const QueryPlanOptimizationSettings & optimization_s
optimizeReadInOrder(*frame.node, nodes);
if (optimization_settings.optimize_projection)
applied_projection |= optimizeUseProjections(*frame.node, nodes);
applied_projection |= optimizeUseAggProjections(*frame.node, nodes);
if (optimization_settings.aggregation_in_order)
optimizeAggregationInOrder(*frame.node, nodes);
@ -140,6 +140,14 @@ void optimizeTreeSecondPass(const QueryPlanOptimizationSettings & optimization_s
continue;
}
if (optimization_settings.optimize_projection)
{
bool applied = optimizeUseNormalProjections(stack, nodes);
applied_projection |= applied;
if (applied && stack.back().next_child == 0)
continue;
}
optimizePrimaryKeyCondition(stack);
enableMemoryBoundMerging(*frame.node, nodes);

View File

@ -12,6 +12,7 @@
#include <Storages/MergeTree/MergeTreeDataSelectExecutor.h>
#include <Storages/StorageReplicatedMergeTree.h>
#include <Common/logger_useful.h>
#include <Processors/QueryPlan/UnionStep.h>
#include <AggregateFunctions/AggregateFunctionCount.h>
#include <Processors/QueryPlan/ReadFromPreparedSource.h>
#include <Processors/Sources/NullSource.h>
@ -167,6 +168,16 @@ struct AggregateProjectionCandidate
size_t sum_marks = 0;
};
struct NormalProjectionCandidate
{
const ProjectionDescription * projection;
MergeTreeDataSelectAnalysisResultPtr merge_tree_projection_select_result_ptr;
MergeTreeDataSelectAnalysisResultPtr merge_tree_normal_select_result_ptr;
size_t sum_marks = 0;
};
ActionsDAGPtr analyzeAggregateProjection(
const AggregateProjectionInfo & info,
ActionsDAG & query_dag,
@ -430,7 +441,7 @@ ActionsDAGPtr analyzeAggregateProjection(
return proj_dag;
}
bool optimizeUseProjections(QueryPlan::Node & node, QueryPlan::Nodes & nodes)
bool optimizeUseAggProjections(QueryPlan::Node & node, QueryPlan::Nodes & nodes)
{
if (node.children.size() != 1)
return false;
@ -724,4 +735,226 @@ bool optimizeUseProjections(QueryPlan::Node & node, QueryPlan::Nodes & nodes)
return true;
}
bool optimizeUseNormalProjections(Stack & stack, QueryPlan::Nodes & nodes)
{
const auto & frame = stack.back();
auto * reading = typeid_cast<ReadFromMergeTree *>(frame.node->step.get());
if (!reading)
return false;
auto iter = stack.rbegin();
while (iter != stack.rend())
{
auto next = std::next(iter);
if (!typeid_cast<FilterStep *>(next->node->step.get()) &&
!typeid_cast<ExpressionStep *>(next->node->step.get()))
break;
iter = next;
}
if (iter == stack.rbegin())
return false;
const auto metadata = reading->getStorageMetadata();
const auto & projections = metadata->projections;
std::vector<const ProjectionDescription *> normal_projections;
for (const auto & projection : projections)
if (projection.type == ProjectionDescription::Type::Normal)
normal_projections.push_back(&projection);
if (normal_projections.empty())
return false;
ActionsDAGPtr dag;
ActionsDAG::NodeRawConstPtrs filter_nodes;
if (!buildAggregatingDAG(*iter->node->children.front(), dag, filter_nodes))
return false;
LOG_TRACE(&Poco::Logger::get("optimizeUseProjections"), "Query DAG: {}", dag->dumpDAG());
const ActionsDAG::Node * filter_node = nullptr;
if (!filter_nodes.empty())
{
filter_node = filter_nodes.front();
if (filter_nodes.size() > 1)
{
FunctionOverloadResolverPtr func_builder_and =
std::make_unique<FunctionToOverloadResolverAdaptor>(
std::make_shared<FunctionAnd>());
filter_node = &dag->addFunction(func_builder_and, std::move(filter_nodes), {});
}
dag->getOutputs().push_back(filter_node);
}
std::list<NormalProjectionCandidate> candidates;
NormalProjectionCandidate * best_candidate = nullptr;
const Block & header = frame.node->step->getOutputStream().header;
const Names & required_columns = reading->getRealColumnNames();
const auto & parts = reading->getParts();
const auto & query_info = reading->getQueryInfo();
ContextPtr context = reading->getContext();
MergeTreeDataSelectExecutor reader(reading->getMergeTreeData());
std::shared_ptr<PartitionIdToMaxBlock> max_added_blocks;
if (context->getSettingsRef().select_sequential_consistency)
{
if (const StorageReplicatedMergeTree * replicated = dynamic_cast<const StorageReplicatedMergeTree *>(&reading->getMergeTreeData()))
max_added_blocks = std::make_shared<PartitionIdToMaxBlock>(replicated->getMaxAddedBlocks());
}
for (const auto * projection : normal_projections)
{
bool has_all_columns = true;
for (const auto & col : required_columns)
{
if (!projection->sample_block.has(col))
{
has_all_columns = false;
break;
}
}
if (!has_all_columns)
continue;
MergeTreeData::DataPartsVector projection_parts;
MergeTreeData::DataPartsVector normal_parts;
for (const auto & part : parts)
{
const auto & created_projections = part->getProjectionParts();
auto it = created_projections.find(projection->name);
if (it != created_projections.end())
projection_parts.push_back(it->second);
else
normal_parts.push_back(part);
}
if (projection_parts.empty())
continue;
ActionDAGNodes added_filter_nodes;
if (filter_node)
added_filter_nodes.nodes.push_back(filter_node);
auto projection_result_ptr = reader.estimateNumMarksToRead(
std::move(projection_parts),
nullptr,
header.getNames(),
metadata,
projection->metadata,
query_info, /// How it is actually used? I hope that for index we need only added_filter_nodes
added_filter_nodes,
context,
context->getSettingsRef().max_threads,
max_added_blocks);
if (projection_result_ptr->error())
continue;
auto & candidate = candidates.emplace_back();
candidate.merge_tree_projection_select_result_ptr = std::move(projection_result_ptr);
candidate.sum_marks += candidate.merge_tree_projection_select_result_ptr->marks();
if (!normal_parts.empty())
{
auto normal_result_ptr = reading->selectRangesToRead(std::move(normal_parts));
if (normal_result_ptr->error())
continue;
if (normal_result_ptr->marks() != 0)
{
candidate.sum_marks += normal_result_ptr->marks();
candidate.merge_tree_normal_select_result_ptr = std::move(normal_result_ptr);
}
}
if (best_candidate == nullptr || best_candidate->sum_marks > candidate.sum_marks)
best_candidate = &candidate;
}
if (!best_candidate)
return false;
auto storage_snapshot = reading->getStorageSnapshot();
auto proj_snapshot = std::make_shared<StorageSnapshot>(
storage_snapshot->storage, storage_snapshot->metadata, storage_snapshot->object_columns); //, storage_snapshot->data);
proj_snapshot->addProjection(best_candidate->projection);
LOG_TRACE(&Poco::Logger::get("optimizeUseProjections"), "Proj snapshot {}", proj_snapshot->getColumns(GetColumnsOptions::Kind::All).toString());
auto projection_reading = reader.readFromParts(
{},
header.getNames(),
proj_snapshot,
query_info,
context,
reading->getMaxBlockSize(),
reading->getNumStreams(),
max_added_blocks,
best_candidate->merge_tree_projection_select_result_ptr,
reading->isParallelReadingEnabled());
if (!projection_reading)
{
Pipe pipe(std::make_shared<NullSource>(proj_snapshot->getSampleBlockForColumns(header.getNames())));
projection_reading = std::make_unique<ReadFromPreparedSource>(std::move(pipe));
}
bool has_nornal_parts = best_candidate->merge_tree_normal_select_result_ptr != nullptr;
if (has_nornal_parts)
reading->setAnalyzedResult(std::move(best_candidate->merge_tree_normal_select_result_ptr));
LOG_TRACE(&Poco::Logger::get("optimizeUseProjections"), "Projection reading header {}", projection_reading->getOutputStream().header.dumpStructure());
projection_reading->setStepDescription(best_candidate->projection->name);
auto & projection_reading_node = nodes.emplace_back(QueryPlan::Node{.step = std::move(projection_reading)});
auto & expr_or_filter_node = nodes.emplace_back();
if (filter_node)
{
expr_or_filter_node.step = std::make_unique<FilterStep>(
projection_reading_node.step->getOutputStream(),
dag,
dag->getOutputs().front()->result_name,
true);
}
else
expr_or_filter_node.step = std::make_unique<ExpressionStep>(
projection_reading_node.step->getOutputStream(),
dag);
expr_or_filter_node.children.push_back(&projection_reading_node);
if (!has_nornal_parts)
{
/// All parts are taken from projection
iter->node->children.front() = &expr_or_filter_node;
//optimizeAggregationInOrder(node, nodes);
}
else
{
auto & union_node = nodes.emplace_back();
DataStreams input_streams = {iter->node->children.front()->step->getOutputStream(), expr_or_filter_node.step->getOutputStream()};
union_node.step = std::make_unique<UnionStep>(std::move(input_streams));
union_node.children = {iter->node->children.front(), &expr_or_filter_node};
iter->node->children.front() = &union_node;
iter->next_child = 0;
stack.resize(iter.base() - stack.begin() + 1);
}
return true;
}
}