optimize-all-path-go (vesoft-inc#5528) (vesoft-inc#2732)

Co-authored-by: jimingquan <[email protected]>

src/graph/context/ast/QueryAstContext.h

@@ -95,6 +95,7 @@ struct GoContext final : AstContext {
   bool joinInput{false};
   // true when $$.tag.prop exist
   bool joinDst{false};
+  bool isSimple{false};
 
   ExpressionProps exprProps;
 

src/graph/executor/algo/AllPathsExecutor.cpp

@@ -12,7 +12,7 @@ DEFINE_uint32(
     100,
     "the number of vids to expand, when this threshold is exceeded, use heuristic expansion");
 DEFINE_uint32(path_threshold_ratio, 2, "threshold for heuristics expansion");
-DEFINE_uint32(path_batch_size, 5000, "number of paths constructed by each thread");
+DEFINE_uint32(path_batch_size, 50000, "number of paths constructed by each thread");
 
 namespace nebula {
 namespace graph {
@@ -156,13 +156,16 @@ folly::Future<Status> AllPathsExecutor::getNeighbors(bool reverse) {
         }
         auto listVal = std::make_shared<Value>(std::move(list));
         auto iter = std::make_unique<GetNeighborsIter>(listVal);
+        time::Duration buildAdjTime;
+        auto key = folly::sformat("buildAdjTime {}step[{}]", reverse ? "reverse " : "", step);
         if (reverse) {
           rightNextStepVids_.clear();
           expandFromRight(iter.get());
         } else {
           leftNextStepVids_.clear();
           expandFromLeft(iter.get());
         }
+        otherStats_.emplace(key, folly::sformat("{}(us)", buildAdjTime.elapsedInUSec()));
         return Status::OK();
       });
 }
@@ -261,6 +264,7 @@ folly::Future<Status> AllPathsExecutor::buildResult() {
   // if key exists, discard the right adjacency's key & values
   // because the right adjacency list may have fewer edges
   //  a->c->o, a->b, c->f, f->o
+  time::Duration mergeAdjTime;
   for (auto& rAdj : rightAdjList_) {
     auto& src = rAdj.first;
     auto iter = leftAdjList_.find(src);
@@ -292,71 +296,106 @@ folly::Future<Status> AllPathsExecutor::buildResult() {
       }
     }
   }
+  otherStats_.emplace("merge_adj_time", folly::sformat("{}(us)", mergeAdjTime.elapsedInUSec()));
+  time::Duration buildPathTime;
   auto future = buildPathMultiJobs();
-  return future.via(runner()).thenValue([this](auto&& resp) {
-    UNUSED(resp);
-    if (!withProp_ || emptyPropVids_.empty()) {
-      finish(ResultBuilder().value(Value(std::move(result_))).build());
-      return folly::makeFuture<Status>(Status::OK());
-    }
-    return getPathProps();
-  });
+  return future.via(runner())
+      .ensure([this, buildPathTime]() {
+        otherStats_.emplace("build_path_time",
+                            folly::sformat("{}(us)", buildPathTime.elapsedInUSec()));
+      })
+      .thenValue([this](auto&& resp) {
+        UNUSED(resp);
+        if (!withProp_ || emptyPropVids_.empty()) {
+          finish(ResultBuilder().value(Value(std::move(result_))).build());
+          return folly::makeFuture<Status>(Status::OK());
+        }
+        return getPathProps();
+      });
 }
 
 folly::Future<Status> AllPathsExecutor::buildPathMultiJobs() {
-  auto pathsPtr = std::make_shared<std::vector<std::vector<Value>>>();
+  auto pathsPtr = std::make_shared<std::vector<NPath*>>();
+  if (threadLocalPtr_.get() == nullptr) {
+    threadLocalPtr_.reset(new std::deque<NPath>());
+  }
   for (auto& vid : leftInitVids_) {
     auto vidIter = leftAdjList_.find(vid);
     if (vidIter == leftAdjList_.end()) {
       continue;
     }
-    auto src = vidIter->first;
+    auto& src = vidIter->first;
     auto& adjEdges = vidIter->second;
     if (adjEdges.empty()) {
       continue;
     }
     pathsPtr->reserve(adjEdges.size() + pathsPtr->size());
     for (auto& edge : adjEdges) {
-      pathsPtr->emplace_back(std::vector<Value>({src, edge}));
+      threadLocalPtr_->emplace_back(NPath(src, edge));
+      pathsPtr->emplace_back(&threadLocalPtr_->back());
     }
   }
   size_t step = 2;
   auto future = doBuildPath(step, 0, pathsPtr->size(), pathsPtr);
-  return future.via(runner()).thenValue([this](std::vector<Row>&& paths) {
+  return future.via(runner()).thenValue([this](std::vector<std::pair<NPath*, Value>>&& paths) {
     memory::MemoryCheckGuard guard;
+
     if (!paths.empty()) {
-      result_.rows.swap(paths);
+      time::Duration convertPathTime;
+      for (auto& path : paths) {
+        result_.rows.emplace_back(convertNPath2Row(path.first, path.second));
+      }
+      otherStats_.emplace("convert_path_time",
+                          folly::sformat("{}(us)", convertPathTime.elapsedInUSec()));
     }
     return Status::OK();
   });
 }
 
-folly::Future<std::vector<Row>> AllPathsExecutor::doBuildPath(
-    size_t step,
-    size_t start,
-    size_t end,
-    std::shared_ptr<std::vector<std::vector<Value>>> pathsPtr) {
-  if (cnt_.load(std::memory_order_relaxed) >= limit_) {
-    return folly::makeFuture<std::vector<Row>>(std::vector<Row>());
+// construct ROW[src1, [e1, v2, e2], v3]
+Row AllPathsExecutor::convertNPath2Row(NPath* path, Value dst) {
+  std::vector<Value> list;
+  NPath* head = path;
+  while (head != nullptr) {
+    list.emplace_back(head->edge);
+    list.emplace_back(head->vertex);
+    head = head->p;
   }
+  Row row;
+  // add src;
+  row.values.emplace_back(list.back());
+  list.pop_back();
+  std::reverse(list.begin(), list.end());
+  List edgeList(std::move(list));
+  row.values.emplace_back(std::move(edgeList));
+  row.values.emplace_back(std::move(dst));
+  return row;
+}
 
+folly::Future<std::vector<std::pair<AllPathsExecutor::NPath*, Value>>>
+AllPathsExecutor::doBuildPath(size_t step,
+                              size_t start,
+                              size_t end,
+                              std::shared_ptr<std::vector<NPath*>> pathsPtr) {
+  if (cnt_.load(std::memory_order_relaxed) >= limit_) {
+    return folly::makeFuture<std::vector<std::pair<NPath*, Value>>>(
+        std::vector<std::pair<NPath*, Value>>());
+  }
+  if (threadLocalPtr_.get() == nullptr) {
+    threadLocalPtr_.reset(new std::deque<NPath>());
+  }
   auto& adjList = leftAdjList_;
-  auto currentPathPtr = std::make_unique<std::vector<Row>>();
-  auto newPathsPtr = std::make_shared<std::vector<std::vector<Value>>>();
+  auto currentStepResult = std::make_unique<std::vector<std::pair<NPath*, Value>>>();
+  auto newPathsPtr = std::make_shared<std::vector<NPath*>>();
 
   for (auto i = start; i < end; ++i) {
-    auto& path = (*pathsPtr)[i];
-    auto& edgeValue = path.back();
+    auto path = (*pathsPtr)[i];
+    auto& edgeValue = path->edge;
     DCHECK(edgeValue.isEdge());
     auto& dst = edgeValue.getEdge().dst;
     auto dstIter = rightInitVids_.find(dst);
     if (dstIter != rightInitVids_.end()) {
-      Row row;
-      row.values.emplace_back(path.front());
-      List edgeList(std::vector<Value>(path.begin() + 1, path.end()));
-      row.values.emplace_back(std::move(edgeList));
-      row.values.emplace_back(*dstIter);
-      currentPathPtr->emplace_back(std::move(row));
+      currentStepResult->emplace_back(std::make_pair(path, *dstIter));
       ++cnt_;
       if (cnt_.load(std::memory_order_relaxed) >= limit_) {
         break;
@@ -379,20 +418,17 @@ folly::Future<std::vector<Row>> AllPathsExecutor::doBuildPath(
             continue;
           }
         }
-        // copy
-        auto newPath = path;
-        newPath.emplace_back(adjIter->first);
-        newPath.emplace_back(edge);
-        newPathsPtr->emplace_back(std::move(newPath));
+        threadLocalPtr_->emplace_back(NPath(path, adjIter->first, edge));
+        newPathsPtr->emplace_back(&threadLocalPtr_->back());
       }
     }
   }
 
   auto newPathsSize = newPathsPtr->size();
   if (step > maxStep_ || newPathsSize == 0) {
-    return folly::makeFuture<std::vector<Row>>(std::move(*currentPathPtr));
+    return folly::makeFuture<std::vector<std::pair<NPath*, Value>>>(std::move(*currentStepResult));
   }
-  std::vector<folly::Future<std::vector<Row>>> futures;
+  std::vector<folly::Future<std::vector<std::pair<NPath*, Value>>>> futures;
   if (newPathsSize < FLAGS_path_batch_size) {
     futures.emplace_back(folly::via(runner(), [this, step, newPathsSize, newPathsPtr]() {
       return doBuildPath(step + 1, 0, newPathsSize, newPathsPtr);
@@ -407,9 +443,10 @@ folly::Future<std::vector<Row>> AllPathsExecutor::doBuildPath(
     }
   }
   return folly::collect(futures).via(runner()).thenValue(
-      [pathPtr = std::move(currentPathPtr)](std::vector<std::vector<Row>>&& paths) {
+      [pathPtr = std::move(currentStepResult)](
+          std::vector<std::vector<std::pair<NPath*, Value>>>&& paths) {
         memory::MemoryCheckGuard guard;
-        std::vector<Row> result = std::move(*pathPtr);
+        std::vector<std::pair<NPath*, Value>> result = std::move(*pathPtr);
         for (auto& path : paths) {
           if (path.empty()) {
             continue;
@@ -441,19 +478,29 @@ folly::Future<Status> AllPathsExecutor::getPathProps() {
   });
 }
 
-bool AllPathsExecutor::hasSameVertices(const std::vector<Value>& edgeList, const Edge& edge) {
+bool AllPathsExecutor::hasSameEdge(NPath* path, const Edge& edge) {
+  NPath* head = path;
+  while (head != nullptr) {
+    if (edge == head->edge) {
+      return true;
+    }
+    head = head->p;
+  }
+  return false;
+}
+
+bool AllPathsExecutor::hasSameVertices(NPath* path, const Edge& edge) {
   if (edge.src == edge.dst) {
     return true;
   }
   auto& vid = edge.dst;
-  auto iter = edgeList.begin() + 1;
-  for (; iter != edgeList.end(); iter++) {
-    if (iter->isEdge()) {
-      auto& edgeVal = iter->getEdge();
-      if (edgeVal.src == vid) {
-        return true;
-      }
+  NPath* head = path;
+  while (head != nullptr) {
+    auto& vertex = head->vertex;
+    if (vertex.getVertex().vid == vid) {
+      return true;
     }
+    head = head->p;
   }
   return false;
 }

src/graph/executor/algo/AllPathsExecutor.h

@@ -5,6 +5,7 @@
 #ifndef GRAPH_EXECUTOR_ALGO_ALLPATHSEXECUTOR_H_
 #define GRAPH_EXECUTOR_ALGO_ALLPATHSEXECUTOR_H_
 
+#include "folly/ThreadLocal.h"
 #include "graph/executor/StorageAccessExecutor.h"
 
 // Using the two-way BFS algorithm, a heuristic algorithm is used in the expansion process
@@ -26,10 +27,10 @@
 // when expanding, if the vid has already been visited, do not visit again
 // leftAdjList_ save result of forward expansion
 // rightAdjList_ save result of backward expansion
-
 namespace nebula {
 namespace graph {
 class AllPaths;
+struct NPath;
 class AllPathsExecutor final : public StorageAccessExecutor {
  public:
   AllPathsExecutor(const PlanNode* node, QueryContext* qctx)
@@ -46,6 +47,17 @@ class AllPathsExecutor final : public StorageAccessExecutor {
   template <typename T = Value>
   using VertexMap = std::unordered_map<Value, std::vector<T>, VertexHash, VertexEqual>;
 
+  struct NPath {
+    NPath* p{nullptr};
+    const Value& vertex;
+    const Value& edge;
+    NPath(const Value& v, const Value& e) : vertex(v), edge(e) {}
+    NPath(NPath* path, const Value& v, const Value& e) : p(path), vertex(v), edge(e) {}
+    NPath(NPath&& v) noexcept : p(v.p), vertex(std::move(v.vertex)), edge(std::move(v.edge)) {}
+    NPath(const NPath& v) : p(v.p), vertex(v.vertex), edge(v.edge) {}
+    ~NPath() {}
+  };
+
  private:
   void buildRequestVids(bool reverse);
 
@@ -59,19 +71,20 @@ class AllPathsExecutor final : public StorageAccessExecutor {
 
   void expandFromRight(GetNeighborsIter* iter);
 
-  folly::Future<std::vector<Row>> doBuildPath(
-      size_t step,
-      size_t start,
-      size_t end,
-      std::shared_ptr<std::vector<std::vector<Value>>> edgeLists);
+  Row convertNPath2Row(NPath* path, Value dst);
+
+  folly::Future<std::vector<std::pair<NPath*, Value>>> doBuildPath(
+      size_t step, size_t start, size_t end, std::shared_ptr<std::vector<NPath*>> paths);
 
   folly::Future<Status> getPathProps();
 
   folly::Future<Status> buildPathMultiJobs();
 
   folly::Future<Status> buildResult();
 
-  bool hasSameVertices(const std::vector<Value>& edgeList, const Edge& edge);
+  bool hasSameEdge(NPath* path, const Edge& edge);
+
+  bool hasSameVertices(NPath* path, const Edge& edge);
 
  private:
   const AllPaths* pathNode_{nullptr};
@@ -94,6 +107,8 @@ class AllPathsExecutor final : public StorageAccessExecutor {
 
   DataSet result_;
   std::vector<Value> emptyPropVids_;
+  class NewTag {};
+  folly::ThreadLocalPtr<std::deque<NPath>, NewTag> threadLocalPtr_;
 };
 }  // namespace graph
 }  // namespace nebula

src/graph/executor/query/ExpandExecutor.cpp

@@ -94,7 +94,8 @@ folly::Future<Status> ExpandExecutor::GetDstBySrc() {
             size = (*result.dsts_ref()).size();
           }
           auto info = util::collectRespProfileData(result.result, hostLatency[i], size);
-          otherStats_.emplace(folly::sformat("resp[{}]", i), folly::toPrettyJson(info));
+          otherStats_.emplace(folly::sformat("step{} resp [{}]", currentStep_, i),
+                              folly::toPrettyJson(info));
         }
         auto result = handleCompleteness(resps, FLAGS_accept_partial_success);
         if (!result.ok()) {

src/graph/planner/ngql/GoPlanner.cpp

@@ -158,6 +158,33 @@ PlanNode* GoPlanner::buildJoinDstPlan(PlanNode* dep) {
   return join;
 }
 
+SubPlan GoPlanner::doSimplePlan() {
+  auto qctx = goCtx_->qctx;
+  size_t step = goCtx_->steps.mSteps();
+  auto* expand = Expand::make(qctx,
+                              startNode_,
+                              goCtx_->space.id,
+                              false,  // random
+                              step,
+                              buildEdgeProps(true));
+  expand->setEdgeTypes(buildEdgeTypes());
+  expand->setColNames({"_expand_vid"});
+  expand->setInputVar(goCtx_->vidsVar);
+
+  auto* dedup = Dedup::make(qctx, expand);
+
+  auto pool = qctx->objPool();
+  auto* newYieldExpr = pool->makeAndAdd<YieldColumns>();
+  newYieldExpr->addColumn(new YieldColumn(ColumnExpression::make(pool, 0)));
+  auto* project = Project::make(qctx, dedup, newYieldExpr);
+  project->setColNames(std::move(goCtx_->colNames));
+
+  SubPlan subPlan;
+  subPlan.root = project;
+  subPlan.tail = expand;
+  return subPlan;
+}
+
 SubPlan GoPlanner::doPlan() {
   auto qctx = goCtx_->qctx;
   auto& from = goCtx_->from;
@@ -275,6 +302,9 @@ StatusOr<SubPlan> GoPlanner::transform(AstContext* astCtx) {
     subPlan.root = subPlan.tail = pt;
     return subPlan;
   }
+  if (goCtx_->isSimple) {
+    return doSimplePlan();
+  }
   return doPlan();
 }
 

src/graph/planner/ngql/GoPlanner.h

@@ -34,6 +34,8 @@ class GoPlanner final : public Planner {
  private:
   SubPlan doPlan();
 
+  SubPlan doSimplePlan();
+
  private:
   std::unique_ptr<VertexProps> buildVertexProps(const ExpressionProps::TagIDPropsMap& propsMap);