Question

虽然我了解Bulking的原理，但我很想知道机器如何从您的编程角度实现这一目标。如何检测多个Traverser在同一节点上，以决定合并和批量处理它们。是否有描述用于检测特定情况需要批量处理的算法。

此外，触发批量的显式步骤是什么。是否可以在遍历中添加任何指令，以使大量操作显式地发生？

Answer 1

膨胀通常与barrier()步骤有关，在TinkerPop的参考文档here中进行了一些讨论。大多数人不会（尽管可以）在Gremlin写作中直接使用barrier()，因为TinkerPop中内置了各种遍历策略（例如LazyBarrierStrategy），试图将它们自动注入遍历的位置他们可能会有所作为。

通过遍历执行barrier()，可以看到在哪里/何时插入explain()步骤：

gremlin> g.V().out().both().explain()
==>Traversal Explanation
=======================================================================================================================================
Original Traversal                 [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]

ConnectiveStrategy           [D]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]
IncidentToAdjacentStrategy   [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]
MatchPredicateStrategy       [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]
RepeatUnrollStrategy         [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]
PathRetractionStrategy       [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]
FilterRankingStrategy        [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]
InlineFilterStrategy         [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]
AdjacentToIncidentStrategy   [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]
CountStrategy                [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), VertexStep(BOTH,vertex)]
LazyBarrierStrategy          [O]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(BOTH,vertex)]
TinkerGraphCountStrategy     [P]   [GraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(BOTH,vertex)]
TinkerGraphStepStrategy      [P]   [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(BOTH,vertex)]
ProfileStrategy              [F]   [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(BOTH,vertex)]
StandardVerificationStrategy [V]   [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(BOTH,vertex)]

Final Traversal                    [TinkerGraphStep(vertex,[]), VertexStep(OUT,vertex), NoOpBarrierStep(2500), VertexStep(BOTH,vertex)]

Answer 2

在此，在上面@stephen评论之后，我只想分享一个博客的链接，其中一个博客深入解释了著名的LazyBarrierStrategy

格雷姆林遍历膨胀（OLTP）

2 个答案: