# Potential performance regressions in Julia 1.8 for special un-precompiled type dispatches and how to fix them

**URL:** <https://discourse.julialang.org/t/potential-performance-regressions-in-julia-1-8-for-special-un-precompiled-type-dispatches-and-how-to-fix-them/86359>\
**Category:** Performance\
**Tags:** performance\
**Created:** [August 25, 2022, 8:27pm UTC](https://discourse.julialang.org/t/potential-performance-regressions-in-julia-1-8-for-special-un-precompiled-type-dispatches-and-how-to-fix-them/86359 "2022-08-25T20:27:47Z")\
**Posts on this page:** 1\
**Showing post:** 6

<div class="post-metadata">

**Author:** ![ranocha](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/ranocha/32/35588_2.png) [@ranocha](https://discourse.julialang.org/u/ranocha)\
**Post date:** [August 26, 2022, 11:47am UTC](https://discourse.julialang.org/t/potential-performance-regressions-in-julia-1-8-for-special-un-precompiled-type-dispatches-and-how-to-fix-them/86359/6 "2022-08-26T11:47:49Z")

</div>

Okay, so I went a bit invalidation hunting this morning:

- Static.jl invalidates quite a lot, see  
[fix invalidations in logging by ranocha · Pull Request #46481 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/pull/46481),  
[fix invalidations for Dicts from Static.jl by ranocha · Pull Request #46490 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/pull/46490),  
[fix invalidations in sort! from Static.jl by ranocha · Pull Request #46491 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/pull/46491),  
[fix invalidations of `isinf` from Static.jl by ranocha · Pull Request #46493 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/pull/46493),  
[fix invalidations in REPLCompletions from Static.jl by ranocha · Pull Request #46494 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/pull/46494),  
[fix invalidations from Static.jl by ranocha · Pull Request #140 · JuliaIO/Tar.jl · GitHub](https://github.com/JuliaIO/Tar.jl/pull/140),  
[fix API invalidations from Static.jl by ranocha · Pull Request #3179 · JuliaLang/Pkg.jl · GitHub](https://github.com/JuliaLang/Pkg.jl/pull/3179)
- Unrolled.jl invalidates a bunch of stuff, see [Unrolled.jl invalidates quite a lot · Issue #12 · cstjean/Unrolled.jl · GitHub](https://github.com/cstjean/Unrolled.jl/issues/12)
- HDF5.jl invalidates a bunch of stuff in the REPL: [hopefully fix invalidations of REPL from HDF5.jl by ranocha · Pull Request #46486 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/pull/46486)
- ChainRulesCore.jl invalidates a bunch of stuff, see [Invalidations from ChainRulesCore Tangent overload on Tail · Issue #576 · JuliaDiff/ChainRulesCore.jl · GitHub](https://github.com/JuliaDiff/ChainRulesCore.jl/issues/576)
- FixedPointNumbers.jl invalidates quite a bit, in particular from LoopVectorization calling `sum(::Vector{Any})`

```julia
inserting reduce_first(::typeof(Base.add_sum), x::FixedPointNumbers.FixedPoint) in FixedPointNumbers at ~/.julia/packages/FixedPointNumbers/HAGk2/src/FixedPointNumbers.jl:295 invalidated:
  backedges: 1: superseding reduce_first(::typeof(Base.add_sum), x) in Base at reduce.jl:394 with MethodInstance for Base.reduce_first(::typeof(Base.add_sum), ::Any) (309 children)

```

- ArrayInterface.jl invalidates parts of Tar.jl: [hopefully fix invalidations from ArrayInterface.jl by ranocha · Pull Request #138 · JuliaIO/Tar.jl · GitHub](https://github.com/JuliaIO/Tar.jl/pull/138), [hopefully fix more invalidations by ranocha · Pull Request #139 · JuliaIO/Tar.jl · GitHub](https://github.com/JuliaIO/Tar.jl/pull/139)
- OrderedCollections.jl invalidates quite a bit

```julia
inserting convert(::Type{OrderedCollections.OrderedDict{K, V}}, d::OrderedCollections.OrderedDict{K, V}) where {K, V} in OrderedCollections at ~/.julia/packages/OrderedCollections/PRayh/src/ordered_dict.jl:110 invalidated:
 backedges: 1: superseding convert(::Type{T}, x::AbstractDict) where T<:AbstractDict in Base at abstractdict.jl:561 with MethodInstance for convert(::Type, ::AbstractDict) (134 children)

```

- LoopVectorization.jl invalidates some code in HDF5.jl and indexing:

```julia
inserting convert(::Type{T}, i::LoopVectorization.UpperBoundedInteger) where T<:Number in LoopVectorization at /home/hendrik/.julia/packages/LoopVectorization/e7fJe/src/reconstruct_loopset.jl:25 invalidated:
 backedges: 1: superseding convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7 with MethodInstance for convert(::Type{UInt64}, ::Integer) (3 children)
            2: superseding convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7 with MethodInstance for convert(::Type{Int64}, ::Integer) (17 children)
            3: superseding convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7 with MethodInstance for convert(::Type{Int32}, ::Integer) (99 children)
 17 mt_cache

```

- Geometry basics also invalidates code in HDF5.jl etc.

```julia
inserting convert(::Type{IT}, x::GeometryBasics.OffsetInteger) where IT<:Integer in GeometryBasics at /home/hendrik/.julia/packages/GeometryBasics/5Sb5M/src/offsetintegers.jl:40 invalidated:
 mt_backedges: 1: signature convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7 (formerly convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7) triggered MethodInstance for Colors._precompile_() (1 children)
               2: signature convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7 (formerly convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7) triggered MethodInstance for parse(::Type{ColorTypes.RGB{FixedPointNumbers.N0f8}}, ::String) (1 children)
               3: signature convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7 (formerly convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7) triggered MethodInstance for Colors._parse_colorant(::String) (1 children)
 backedges: 1: superseding convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7 with MethodInstance for convert(::Type{Int64}, ::Integer) (9 children)
            2: superseding convert(::Type{T}, x::Number) where T<:Number in Base at number.jl:7 with MethodInstance for convert(::Type{Int32}, ::Integer) (91 children)

```

- ForwardDiff.jl invalidates some string code: [fix type instability/invalidations from `nextind` by ranocha · Pull Request #46489 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/pull/46489)
- StaticArrays.jl also invalidates quite a bit, e.g.,

```julia
inserting similar(::Type{A}, shape::Union{Tuple{SOneTo, Vararg{Union{Integer, Base.OneTo, SOneTo}}}, Tuple{Union{Integer, Base.OneTo}, SOneTo, Vararg{Union{Integer, Base.OneTo, SOneTo}}}, Tuple{Union{Integer, Base.OneTo}, Union{Integer, Base.OneTo}, SOneTo, Vararg{Union{Integer, Base.OneTo, SOneTo}}}}) where A<:AbstractArray in StaticArrays at ~/.julia/packages/StaticArrays/68nRv/src/abstractarray.jl:156 invalidated:
 mt_backedges: 1: signature Tuple{typeof(similar), Type{Array{Union{Int64, Symbol}, _A}} where _A, Tuple{Union{Integer, AbstractUnitRange}}} triggered MethodInstance for similar(::Type{Array{Union{Int64, Symbol}, _A}}, ::Union{Integer, AbstractUnitRange}) where _A (0 children)
               2: signature Tuple{typeof(similar), Type{Array{Union{Int64, Symbol}, _A}} where _A, Any} triggered MethodInstance for Base._array_for(::Type{Union{Int64, Symbol}}, ::Base.HasShape, ::Any) (0 children)
               3: signature Tuple{typeof(similar), Type{Array{Any, _A}} where _A, Tuple{Union{Integer, AbstractUnitRange}}} triggered MethodInstance for similar(::Type{Array{Any, _A}}, ::Union{Integer, AbstractUnitRange}) where _A (0 children)
               4: signature Tuple{typeof(similar), Type{Array{Any, _A}} where _A, Any} triggered MethodInstance for Base._array_for(::Type{Any}, ::Base.HasShape, ::Any) (0 children)
               5: signature Tuple{typeof(similar), Type{Array{Base.PkgId, _A}} where _A, Tuple{Union{Integer, AbstractUnitRange}}} triggered MethodInstance for similar(::Type{Array{Base.PkgId, _A}}, ::Union{Integer, AbstractUnitRange}) where _A (0 children)
               6: signature Tuple{typeof(similar), Type{Array{Base.PkgId, _A}} where _A, Any} triggered MethodInstance for Base._array_for(::Type{Base.PkgId}, ::Base.HasShape, ::Any) (0 children)
               7: signature Tuple{typeof(similar), Type{Array{Union{Int64, Symbol}, _A}} where _A, Tuple{Union{Integer, AbstractUnitRange}}} triggered MethodInstance for similar(::Type{Array{Union{Int64, Symbol}, _A}}, ::Tuple{Union{Integer, Base.OneTo}}) where _A (9 children)
               8: signature Tuple{typeof(similar), Type{Array{Base.PkgId, _A}} where _A, Tuple{Union{Integer, AbstractUnitRange}}} triggered MethodInstance for similar(::Type{Array{Base.PkgId, _A}}, ::Tuple{Union{Integer, Base.OneTo}}) where _A (9 children)
               9: signature Tuple{typeof(similar), Type{Array{Any, _A}} where _A, Tuple{Union{Integer, AbstractUnitRange}}} triggered MethodInstance for similar(::Type{Array{Any, _A}}, ::Tuple{Union{Integer, Base.OneTo}}) where _A (136 children)

```

- There are of course more invalidations, but they seem to be less severe, e.g.,  
[hopefully fix invalidations in API from AbstractFFTs by ranocha · Pull Request #3180 · JuliaLang/Pkg.jl · GitHub](https://github.com/JuliaLang/Pkg.jl/pull/3180)

However, I would have expected that these invalidations happen also with Julia v1.7 - or do I miss something?

---

_[View the full topic](https://discourse.julialang.org/t/potential-performance-regressions-in-julia-1-8-for-special-un-precompiled-type-dispatches-and-how-to-fix-them/86359)._