Details
Minor Description
In the class org.apache.lucene.queries.function.valuesource.MultiFunction there is the following method signature (line 52)
public static boolean allExists(int doc, FunctionValues... values)
this method is called from the class org.apache.lucene.queries.function.valuesource.DualFloatFunction (line 68)
public boolean exists(int doc)
{ return MultiFunction.allExists(doc, aVals, bVals); }Because MultiFunction.allExists uses Java varargs syntax ("...") a new FunctionValues[] object will be created every time this call takes place.
The problem is that the call takes place in a document level function, which means that it will create new objects in the heap for every document in the query results.
for example if you use the following boost function (where ds and dc1 are both TrieDateField)
bf=min(ms(ds,dc1),604800000)
You will get extra objects created for each document in the result set, which has a big impact on performance and memory usage if you are searching a large result set.
