Package org.apache.lucene.sandbox.search

Class QueryProfilerTree

  • class QueryProfilerTree
extends java.lang.Object
    This class tracks the dependency tree for queries (scoring and rewriting) and generates QueryProfilerBreakdown for each node in the tree.

    • Field Detail

      • tree

        private final java.util.ArrayList<java.util.ArrayList<java.lang.Integer>> tree
        Maps the Query to it's list of children. This is basically the dependency tree

      • queries

        private final java.util.ArrayList<Query> queries
        A list of the original queries, keyed by index position

      • roots

        private final java.util.ArrayList<java.lang.Integer> roots
        A list of top-level "roots". Each root can have its own tree of profiles

      • stack

        private final java.util.Deque<java.lang.Integer> stack
        A temporary stack used to record where we are in the dependency tree.

      • currentToken

        private int currentToken

      • rewriteTime

        private long rewriteTime
        Rewrite time

      • rewriteScratch

        private long rewriteScratch

    • Constructor Detail

      • QueryProfilerTree

        public QueryProfilerTree()

    • Method Detail

      • getProfileBreakdown

        public QueryProfilerBreakdown getProfileBreakdown​(Query query)
        Returns a QueryProfilerBreakdown for a scoring query. Scoring queries (e.g. those that are past the rewrite phase and are now being wrapped by createWeight() ) follow a recursive progression. We can track the dependency tree by a simple stack

        The only hiccup is that the first scoring query will be identical to the last rewritten query, so we need to take special care to fix that

        Parameters:
        query - The scoring query we wish to profile
        Returns:
        A ProfileBreakdown for this query

      • addDependencyNode

        private QueryProfilerBreakdown addDependencyNode​(Query query,
                                                 int token)
        Helper method to add a new node to the dependency tree.

        Initializes a new list in the dependency tree, saves the query and generates a new QueryProfilerBreakdown to track the timings of this query.

        Parameters:
        query - The query to profile
        token - The assigned token for this query
        Returns:
        A QueryProfilerBreakdown to profile this query

      • pollLast

        public void pollLast()
        Removes the last (e.g. most recent) value on the stack

      • getTree

        public java.util.List<QueryProfilerResult> getTree()
        After the query has been run and profiled, we need to merge the flat timing map with the dependency graph to build a data structure that mirrors the original query tree
        Returns:
        a hierarchical representation of the profiled query tree

      • doGetTree

        private QueryProfilerResult doGetTree​(int token)
        Recursive helper to finalize a node in the dependency tree
        Parameters:
        token - The node we are currently finalizing
        Returns:
        A hierarchical representation of the tree inclusive of children at this level

      • getTypeFromQuery

        private java.lang.String getTypeFromQuery​(Query query)

      • getDescriptionFromQuery

        private java.lang.String getDescriptionFromQuery​(Query query)

      • updateParent

        private void updateParent​(int childToken)
        Internal helper to add a child to the current parent node
        Parameters:
        childToken - The child to add to the current parent

      • startRewriteTime

        public void startRewriteTime()
        Begin timing a query for a specific Timing context

      • stopAndAddRewriteTime

        public long stopAndAddRewriteTime()
        Halt the timing process and add the elapsed rewriting time. startRewriteTime() must be called for a particular context prior to calling stopAndAddRewriteTime(), otherwise the elapsed time will be negative and nonsensical
        Returns:
        The elapsed time

      • getRewriteTime

        public long getRewriteTime()