Using StaticArrays causes much more allocations than using normal arrays

[ufechner7]

Describe the bug 🐞

Using StaticArrays with the DFBDF solver makes the allocations of my test case increase from 87 bytes to 2714 bytes per iteration, even though it should be supported and there is even a test case for this

Expected behavior

No increase in allocations, preferably a decrease to zero.

Minimal Reproducible Example 👇

using OrdinaryDiffEq, StaticArrays

STATIC_ARRAYS::Bool = true
if STATIC_ARRAYS
    const G_EARTH  = SA[0.0, 0.0, -9.81] # gravitational acceleration
else
    const G_EARTH  = [0.0, 0.0, -9.81] # gravitational acceleration
end
const dt = 0.05
const t_final = 10.0
  
# Example one: Falling mass
# State vector y   = mass.pos, mass.vel
# Derivative   yd  = mass.vel, mass.acc
# Residual     res = (y.vel - yd.vel), (yd.acc - G_EARTH)     
function res!(res, yd, y, p, time)
    @views res[1:3] .= y[4:6] .- yd[1:3]
    @views res[4:6] .= yd[4:6] .- G_EARTH
    nothing
end

struct Result
    time::Vector{Float64}
    pos_z::Vector{Float64}
    vel_z::Vector{Float64}
end
function Result(t_final)
    n=Int64(round(t_final/dt+1))
    Result(zeros(n), zeros(n), zeros(n))
end

function solve!(res, integrator, dt, t_final)
    for (i,t) in pairs(0:dt:t_final)
        res.time[i] = t
        step!(integrator, dt, true)
        res.pos_z[i] = integrator.u[3]
        res.vel_z[i] = integrator.u[6]
    end
    nothing
end

function init()
    vel_0 = [0.0, 0.0, 50.0]    # Initial velocity
    pos_0 = [0.0, 0.0,  0.0]    # Initial position
    acc_0 = [0.0, 0.0, -9.81]   # Initial acceleration
    y0 = append!(pos_0, vel_0)  # Initial pos, vel
    yd0 = append!(vel_0, acc_0) # Initial vel, acc
    if STATIC_ARRAYS
        y0 = MVector{6}(y0)
        yd0 = MVector{6}(yd0)
    end
    println(typeof(y0))

    # solver = DImplicitEuler(autodiff=false)            # 321 bytes, 0.341 ms
    solver = DFBDF(autodiff=false)                       #  87 bytes, 0.315 ms
    # solver = DABDF2(autodiff=false)                    #   1 bytes, 0.319 ms
    
    tspan   = (0.0, t_final) 
    abstol  = 0.0006 # max error in m/s and m
    reltol=0.001 #* ones(length(y0))
    s = nothing

    prob    = DAEProblem(res!, yd0, y0, tspan, s)
    integrator = OrdinaryDiffEq.init(prob, solver; abstol, reltol, save_everystep=false)
end

integrator=init()
res=Result(t_final)
@time solve!(res, integrator, dt, t_final)
integrator=init()
res=Result(t_final)
bytes = @allocated solve!(res, integrator, dt, t_final)
n=Int64(round(t_final/dt+1))
println("Allocated $(Int64(round(bytes/n))) bytes per iteration!")
integrator=init()
res=Result(t_final)
@timev solve!(res, integrator, dt, t_final)

If I run it, it gives me 2714 bytes per iteration with STATIC_ARRAYS=true and 87 bytes per iteration with STATIC_ARRAYS=false.

Environment (please complete the following information):

• Output of using Pkg; Pkg.status()

(temp) pkg> st
Status `~/repos/temp/Project.toml`
  [1dea7af3] OrdinaryDiffEq v6.74.1
  [90137ffa] StaticArrays v1.9.3

• Output of using Pkg; Pkg.status(; mode = PKGMODE_MANIFEST)

julia> using Pkg; Pkg.status(; mode = PKGMODE_MANIFEST)
Status `~/repos/temp/Manifest.toml`
  [47edcb42] ADTypes v0.2.7
  [7d9f7c33] Accessors v0.1.36
  [79e6a3ab] Adapt v4.0.4
⌅ [ec485272] ArnoldiMethod v0.2.0
  [4fba245c] ArrayInterface v7.9.0
  [4c555306] ArrayLayouts v1.9.1
  [62783981] BitTwiddlingConvenienceFunctions v0.1.5
  [2a0fbf3d] CPUSummary v0.2.4
  [d360d2e6] ChainRulesCore v1.23.0
  [fb6a15b2] CloseOpenIntervals v0.1.12
  [38540f10] CommonSolve v0.2.4
  [bbf7d656] CommonSubexpressions v0.3.0
  [34da2185] Compat v4.14.0
  [a33af91c] CompositionsBase v0.1.2
  [2569d6c7] ConcreteStructs v0.2.3
  [187b0558] ConstructionBase v1.5.5
  [adafc99b] CpuId v0.3.1
  [9a962f9c] DataAPI v1.16.0
  [864edb3b] DataStructures v0.18.18
  [e2d170a0] DataValueInterfaces v1.0.0
  [2b5f629d] DiffEqBase v6.149.0
  [163ba53b] DiffResults v1.1.0
  [b552c78f] DiffRules v1.15.1
  [ffbed154] DocStringExtensions v0.9.3
  [4e289a0a] EnumX v1.0.4
⌃ [f151be2c] EnzymeCore v0.6.6
  [d4d017d3] ExponentialUtilities v1.26.1
  [e2ba6199] ExprTools v0.1.10
  [7034ab61] FastBroadcast v0.2.8
  [9aa1b823] FastClosures v0.3.2
  [29a986be] FastLapackInterface v2.0.2
  [1a297f60] FillArrays v1.10.0
  [6a86dc24] FiniteDiff v2.23.0
  [f6369f11] ForwardDiff v0.10.36
  [069b7b12] FunctionWrappers v1.1.3
  [77dc65aa] FunctionWrappersWrappers v0.1.3
  [46192b85] GPUArraysCore v0.1.6
  [c145ed77] GenericSchur v0.5.4
  [86223c79] Graphs v1.9.0
  [3e5b6fbb] HostCPUFeatures v0.1.16
  [615f187c] IfElse v0.1.1
  [d25df0c9] Inflate v0.1.4
  [3587e190] InverseFunctions v0.1.13
  [92d709cd] IrrationalConstants v0.2.2
  [82899510] IteratorInterfaceExtensions v1.0.0
  [692b3bcd] JLLWrappers v1.5.0
  [ef3ab10e] KLU v0.6.0
  [ba0b0d4f] Krylov v0.9.5
  [10f19ff3] LayoutPointers v0.1.15
  [5078a376] LazyArrays v1.9.0
  [d3d80556] LineSearches v7.2.0
  [7ed4a6bd] LinearSolve v2.28.0
  [2ab3a3ac] LogExpFunctions v0.3.27
  [bdcacae8] LoopVectorization v0.12.169
  [1914dd2f] MacroTools v0.5.13
  [d125e4d3] ManualMemory v0.1.8
  [a3b82374] MatrixFactorizations v2.1.0
  [bb5d69b7] MaybeInplace v0.1.2
  [46d2c3a1] MuladdMacro v0.2.4
  [d41bc354] NLSolversBase v7.8.3
  [77ba4419] NaNMath v1.0.2
  [8913a72c] NonlinearSolve v3.9.1
  [6fe1bfb0] OffsetArrays v1.13.0
  [bac558e1] OrderedCollections v1.6.3
  [1dea7af3] OrdinaryDiffEq v6.74.1
  [65ce6f38] PackageExtensionCompat v1.0.2
  [d96e819e] Parameters v0.12.3
  [f517fe37] Polyester v0.7.12
  [1d0040c9] PolyesterWeave v0.2.1
  [d236fae5] PreallocationTools v0.4.20
  [aea7be01] PrecompileTools v1.2.1
  [21216c6a] Preferences v1.4.3
  [3cdcf5f2] RecipesBase v1.3.4
  [731186ca] RecursiveArrayTools v3.13.0
  [f2c3362d] RecursiveFactorization v0.2.21
  [189a3867] Reexport v1.2.2
  [ae029012] Requires v1.3.0
  [7e49a35a] RuntimeGeneratedFunctions v0.5.12
  [94e857df] SIMDTypes v0.1.0
  [476501e8] SLEEFPirates v0.6.42
  [0bca4576] SciMLBase v2.31.0
  [c0aeaf25] SciMLOperators v0.3.8
  [53ae85a6] SciMLStructures v1.1.0
  [efcf1570] Setfield v1.1.1
  [727e6d20] SimpleNonlinearSolve v1.7.0
  [699a6c99] SimpleTraits v0.9.4
  [ce78b400] SimpleUnPack v1.1.0
  [47a9eef4] SparseDiffTools v2.17.0
  [e56a9233] Sparspak v0.3.9
  [276daf66] SpecialFunctions v2.3.1
  [aedffcd0] Static v0.8.10
  [0d7ed370] StaticArrayInterface v1.5.0
  [90137ffa] StaticArrays v1.9.3
  [1e83bf80] StaticArraysCore v1.4.2
  [7792a7ef] StrideArraysCore v0.5.2
  [2efcf032] SymbolicIndexingInterface v0.3.15
  [3783bdb8] TableTraits v1.0.1
  [bd369af6] Tables v1.11.1
  [8290d209] ThreadingUtilities v0.5.2
  [a759f4b9] TimerOutputs v0.5.23
  [d5829a12] TriangularSolve v0.1.21
  [410a4b4d] Tricks v0.1.8
  [781d530d] TruncatedStacktraces v1.4.0
  [3a884ed6] UnPack v1.0.2
  [3d5dd08c] VectorizationBase v0.21.65
  [19fa3120] VertexSafeGraphs v0.2.0
  [1d5cc7b8] IntelOpenMP_jll v2024.0.2+0
  [856f044c] MKL_jll v2024.0.0+0
  [efe28fd5] OpenSpecFun_jll v0.5.5+0
  [0dad84c5] ArgTools v1.1.1
  [56f22d72] Artifacts
  [2a0f44e3] Base64
  [ade2ca70] Dates
  [8ba89e20] Distributed
  [f43a241f] Downloads v1.6.0
  [7b1f6079] FileWatching
  [9fa8497b] Future
  [b77e0a4c] InteractiveUtils
  [4af54fe1] LazyArtifacts
  [b27032c2] LibCURL v0.6.4
  [76f85450] LibGit2
  [8f399da3] Libdl
  [37e2e46d] LinearAlgebra
  [56ddb016] Logging
  [d6f4376e] Markdown
  [a63ad114] Mmap
  [ca575930] NetworkOptions v1.2.0
  [44cfe95a] Pkg v1.10.0
  [de0858da] Printf
  [3fa0cd96] REPL
  [9a3f8284] Random
  [ea8e919c] SHA v0.7.0
  [9e88b42a] Serialization
  [1a1011a3] SharedArrays
  [6462fe0b] Sockets
  [2f01184e] SparseArrays v1.10.0
  [10745b16] Statistics v1.10.0
  [4607b0f0] SuiteSparse
  [fa267f1f] TOML v1.0.3
  [a4e569a6] Tar v1.10.0
  [8dfed614] Test
  [cf7118a7] UUIDs
  [4ec0a83e] Unicode
  [e66e0078] CompilerSupportLibraries_jll v1.1.0+0
  [deac9b47] LibCURL_jll v8.4.0+0
  [e37daf67] LibGit2_jll v1.6.4+0
  [29816b5a] LibSSH2_jll v1.11.0+1
  [c8ffd9c3] MbedTLS_jll v2.28.2+1
  [14a3606d] MozillaCACerts_jll v2023.1.10
  [4536629a] OpenBLAS_jll v0.3.23+4
  [05823500] OpenLibm_jll v0.8.1+2
  [bea87d4a] SuiteSparse_jll v7.2.1+1
  [83775a58] Zlib_jll v1.2.13+1
  [8e850b90] libblastrampoline_jll v5.8.0+1
  [8e850ede] nghttp2_jll v1.52.0+1
  [3f19e933] p7zip_jll v17.4.0+2
Info Packages marked with ⌃ and ⌅ have new versions available. Those with ⌃ may be upgradable, but those with ⌅ are restricted by compatibility constraints from upgrading. To see why use `status --outdated -m`

• Output of versioninfo()

Julia Version 1.10.2
Commit bd47eca2c8a (2024-03-01 10:14 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 32 × AMD Ryzen 9 7950X 16-Core Processor
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-15.0.7 (ORCJIT, znver3)
Threads: 1 default, 0 interactive, 1 GC (on 32 virtual cores)
Environment:
  LD_LIBRARY_PATH = /lib:/usr/lib:/usr/local/lib

Additional context

Same problem with other solvers like DImplicitEuler.