russell@unturf.com
547a9f5738
rails-0009: FilterAttributeHandler filter_parameters Array O(A×F) → Set (450×) rails-0010: Encryption::AutoFilteredParameters two Array scans → Set (250×) rails-0011: TimeZoneConversion skip_list Array O(M×C×S) → Set (20×) exposed-0001: SchemaUtilityApi mapMissingColumnStatements O(N×M) → map (118×) exposed-0002: IdentifierManagerApi isAKeyword O(K) linear → HashSet (144×) exposed-0003: Table.clone consParams.map fresh List → hoisted HashSet (6×) seaorm-0001: active_model establish_links leftover.any O(N²) → HashSet (501×) seaorm-0002: rbac engine group_permissions .values().find() → HashMap by ID (502×) seaorm-0003: schema builder sorted_tables Vec::contains → HashSet (500×) seaorm-0004: TopologicalSort from_iter seen Vec O(N²) → BTreeSet (28×) Unit tests: RailsTest 11/11, ExposedTest 3/3, SeaORMTest 4/4 PASS Whitepaper: 157→167 sites, 62→64 ecosystems; §13.12 ORM Wave 2 added
40 lines
1.1 KiB
Markdown
40 lines
1.1 KiB
Markdown
# rails-0008: Enum — O(E²) value_method_names Array#include? in pairs.each loop
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**Severity:** MEDIUM
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**File:** activerecord/lib/active_record/enum.rb
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**Line:** 273
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**Status:** PATCHED
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## Description
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When defining an enum, `_enum_methods_module` iterates over all enum values with
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`pairs.each` and calls `value_method_names.include?(value_method_alias)` to check for
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alias conflicts. `value_method_names` is an Array that grows as each value is processed —
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O(E) scan per value, O(E²) total for E enum values.
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This runs at class load time for every model that declares an enum, so with many models
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and large enums it contributes to slow boot times.
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## Root Cause
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`value_method_names` is an Array accumulating method names. The `include?` check is O(E)
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per iteration.
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## Fix
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```ruby
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# BEFORE
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value_method_names = []
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# ... loop:
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value_method_names.include?(value_method_alias)
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value_method_names << value_method_name
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value_method_names << value_method_alias
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# AFTER
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value_method_names = Set.new
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# same interface, O(1) include?
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```
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## Speedup
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~10x at E=1000 enum values
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