CyclopsMC / CyclopsCore / 34051127524

31%

master-1.21: 31%

Pull #238

github

Hash data components only for stacks that carry a patch

A component map hashes its prototype alongside its patch, and the prototype is
the item's default components. The item is already in the hash, so hashing its
defaults again distinguishes nothing while walking the whole default map. For a
plain stack, which carries no patch at all, that walk was the entire cost of the
hash, and plain stacks are what most of a storage network consists of.

This stays consistent with equality because PatchedDataComponentMap keeps its
patch sanitized: setting a component to its default removes it from the patch
rather than storing it. Two stacks of one item therefore have equal components
exactly when they have equal patches.

Vanilla can only report an empty patch by building one, which is free for
exactly the stacks this catches, so the common implementation does that and
NeoForge overrides it with the direct check.

Measured on the IntegratedDynamics index benchmarks, over 5000 plain stacks
distinct by item and count:

  index_lookup_exact  0.002014 -> 0.000988 ms/op
  index_modification  0.001276 -> 0.000582 ms/op

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Mxjin31W1Lmq5XK1CCe84v

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