Performance Enhancements Resources

Jython benchmarks (from PyPy's suite):

Plots of microbenchmarks (also from PyPy):


jbaker & thobe's JavaOne '08 talk: Jython Implementing Dynamic Language Features For The Java Ecosystem

Allocation/GC Expense

Our algorithms are not always the problem, sometimes it's memory {de}allocations that slow you down

  • dicts/stringmap

PyStringMap/PyDictionary pay a penalty on allocation now that they're backed by ConcurrentHashMap. We could probably tweak the ConcurrentHashMap initialCapacity, concurrentLevel to reduce this cost

  • Frames

Frames are allocated for every Python method call, which is a GC expense. CPython (and JRuby?) recycle frame objects. Reducing the number of fields on the frame can also help (but this likely isn't possible)

Advanced Compiler

Modules to rewrite in Java

  • _heapq
  • select
  • socket
  • unicodedata

iterlen support

Adds a length hint to various objects, mainly for smarter allocation during map and list. See test_iterlen