Module org.apache.lucene.sandbox
Package org.apache.lucene.sandbox.search

Class QueryProfilerTree

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

  • Field Details

    • breakdowns

      private final ArrayList<QueryProfilerBreakdown> breakdowns

    • tree

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

    • queries

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

    • roots

      private final IntArrayList roots
      A list of top-level "roots". Each root can have its own tree of profiles

    • stack

      private final Deque<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 Details

    • QueryProfilerTree

      public QueryProfilerTree()

  • Method Details

    • 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

    • createProfileBreakdown

      private QueryProfilerBreakdown createProfileBreakdown()

    • pollLast

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

    • getTree

      public 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 String getTypeFromQuery(Query query)

    • getDescriptionFromQuery

      private 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()