Benchmarks
Here are some simple benchmarks. Take them with a grain of salt since they run on virtual machines in the cloud to generate the documentation automatically.
First-derivative operators
Periodic domains
Let's set up some benchmark code.
using BenchmarkTools
using LinearAlgebra, SparseArrays
using SummationByPartsOperators, DiffEqOperators
BLAS.set_num_threads(1) # make sure that BLAS is serial to be fair
T = Float64
xmin, xmax = T(0), T(1)
D_SBP = periodic_derivative_operator(derivative_order=1, accuracy_order=2,
xmin=xmin, xmax=xmax, N=100)
x = grid(D_SBP)
D_DEO = CenteredDifference(derivative_order(D_SBP), accuracy_order(D_SBP),
step(x), length(x)) * PeriodicBC(eltype(D_SBP))
D_sparse = sparse(D_SBP)
u = randn(eltype(D_SBP), length(x)); du = similar(u);
@show D_SBP * u ≈ D_DEO * u ≈ D_sparse * u
function doit(D, text, du, u)
println(text)
sleep(0.1)
show(stdout, MIME"text/plain"(), @benchmark mul!($du, $D, $u))
println()
end
doit (generic function with 1 method)
First, we benchmark the implementation from SummationByPartsOperators.jl.
doit(D_SBP, "D_SBP:", du, u)
D_SBP:
BenchmarkTools.Trial: 10000 samples with 995 evaluations.
Range (min … max): 28.707 ns … 50.144 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 29.633 ns ┊ GC (median): 0.00%
Time (mean ± σ): 29.933 ns ± 1.491 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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28.7 ns Histogram: frequency by time 37.5 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
Next, we compare this to the runtime obtained using a sparse matrix representation of the derivative operator. Depending on the hardware etc., this can be an order of magnitude slower than the optimized implementation from SummationByPartsOperators.jl.
doit(D_sparse, "D_sparse:", du, u)
D_sparse:
BenchmarkTools.Trial: 10000 samples with 641 evaluations.
Range (min … max): 189.949 ns … 303.874 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 196.857 ns ┊ GC (median): 0.00%
Time (mean ± σ): 198.552 ns ± 6.194 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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190 ns Histogram: frequency by time 215 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
Finally, we benchmark the implementation of the same derivative operator in DiffEqOperators.jl.
doit(D_DEO, "D_DEO:", du, u)
D_DEO:
┌ Warning: #= /home/runner/.julia/packages/DiffEqOperators/lHq9u/src/derivative_operators/convolutions.jl:412 =#:
│ `LoopVectorization.check_args` on your inputs failed; running fallback `@inbounds @fastmath` loop instead.
│ Use `warn_check_args=false`, e.g. `@turbo warn_check_args=false ...`, to disable this warning.
└ @ DiffEqOperators ~/.julia/packages/LoopVectorization/tIJUA/src/condense_loopset.jl:1166
┌ Warning: #= /home/runner/.julia/packages/DiffEqOperators/lHq9u/src/derivative_operators/convolutions.jl:460 =#:
│ `LoopVectorization.check_args` on your inputs failed; running fallback `@inbounds @fastmath` loop instead.
│ Use `warn_check_args=false`, e.g. `@turbo warn_check_args=false ...`, to disable this warning.
└ @ DiffEqOperators ~/.julia/packages/LoopVectorization/tIJUA/src/condense_loopset.jl:1166
BenchmarkTools.Trial: 10000 samples with 92 evaluations.
Range (min … max): 799.207 ns … 138.891 μs ┊ GC (min … max): 0.00% … 56.12%
Time (median): 822.402 ns ┊ GC (median): 0.00%
Time (mean ± σ): 887.817 ns ± 2.121 μs ┊ GC (mean ± σ): 4.48% ± 2.04%
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▅██████████████████████████████████████████▇▇▇██▇▆▇▇██▇▇▇▇▇▆▆ █
799 ns Histogram: log(frequency) by time 996 ns <
Memory estimate: 416 bytes, allocs estimate: 6.
These results were obtained using the following versions.
using InteractiveUtils
versioninfo()
using Pkg
Pkg.status(["SummationByPartsOperators", "DiffEqOperators"],
mode=PKGMODE_MANIFEST)
Julia Version 1.6.7
Commit 3b76b25b64 (2022-07-19 15:11 UTC)
Platform Info:
OS: Linux (x86_64-pc-linux-gnu)
CPU: AMD EPYC 7763 64-Core Processor
WORD_SIZE: 64
LIBM: libopenlibm
LLVM: libLLVM-11.0.1 (ORCJIT, generic)
Environment:
JULIA_PKG_SERVER_REGISTRY_PREFERENCE = eager
Status `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl/docs/Manifest.toml`
[9fdde737] DiffEqOperators v4.45.0
[9f78cca6] SummationByPartsOperators v0.5.70 `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl`
Bounded domains
We start again by setting up some benchmark code.
using BenchmarkTools
using LinearAlgebra, SparseArrays
using SummationByPartsOperators, BandedMatrices
BLAS.set_num_threads(1) # make sure that BLAS is serial to be fair
T = Float64
xmin, xmax = T(0), T(1)
D_SBP = derivative_operator(MattssonNordström2004(), derivative_order=1,
accuracy_order=6, xmin=xmin, xmax=xmax, N=10^3)
D_sparse = sparse(D_SBP)
D_banded = BandedMatrix(D_SBP)
u = randn(eltype(D_SBP), size(D_SBP, 1)); du = similar(u);
@show D_SBP * u ≈ D_sparse * u ≈ D_banded * u
function doit(D, text, du, u)
println(text)
sleep(0.1)
show(stdout, MIME"text/plain"(), @benchmark mul!($du, $D, $u))
println()
end
doit (generic function with 1 method)
First, we benchmark the implementation from SummationByPartsOperators.jl.
doit(D_SBP, "D_SBP:", du, u)
D_SBP:
BenchmarkTools.Trial: 10000 samples with 200 evaluations.
Range (min … max): 405.355 ns … 639.595 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 409.310 ns ┊ GC (median): 0.00%
Time (mean ± σ): 413.050 ns ± 12.665 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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405 ns Histogram: frequency by time 457 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
Again, we compare this to a representation of the derivative operator as a sparse matrix. No surprise - it is again much slower, as in periodic domains.
doit(D_sparse, "D_sparse:", du, u)
D_sparse:
BenchmarkTools.Trial: 10000 samples with 7 evaluations.
Range (min … max): 4.650 μs … 8.344 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 4.696 μs ┊ GC (median): 0.00%
Time (mean ± σ): 4.743 μs ± 233.698 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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4.65 μs Histogram: log(frequency) by time 5.84 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
FInally, we compare it to a representation as banded matrix. Disappointingly, this is still much slower than the optimized implementation from SummationByPartsOperators.jl.
doit(D_banded, "D_banded:", du, u)
D_banded:
BenchmarkTools.Trial: 10000 samples with 5 evaluations.
Range (min … max): 6.640 μs … 12.776 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 6.660 μs ┊ GC (median): 0.00%
Time (mean ± σ): 6.743 μs ± 403.719 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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6.64 μs Histogram: log(frequency) by time 8.65 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
These results were obtained using the following versions.
using InteractiveUtils
versioninfo()
using Pkg
Pkg.status(["SummationByPartsOperators", "BandedMatrices"],
mode=PKGMODE_MANIFEST)
Julia Version 1.6.7
Commit 3b76b25b64 (2022-07-19 15:11 UTC)
Platform Info:
OS: Linux (x86_64-pc-linux-gnu)
CPU: AMD EPYC 7763 64-Core Processor
WORD_SIZE: 64
LIBM: libopenlibm
LLVM: libLLVM-11.0.1 (ORCJIT, generic)
Environment:
JULIA_PKG_SERVER_REGISTRY_PREFERENCE = eager
Status `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl/docs/Manifest.toml`
[aae01518] BandedMatrices v0.17.18
[9f78cca6] SummationByPartsOperators v0.5.70 `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl`
Dissipation operators
We follow the same structure as before. At first, we set up some benchmark code.
using BenchmarkTools
using LinearAlgebra, SparseArrays
using SummationByPartsOperators, BandedMatrices
BLAS.set_num_threads(1) # make sure that BLAS is serial to be fair
T = Float64
xmin, xmax = T(0), T(1)
D_SBP = derivative_operator(MattssonNordström2004(), derivative_order=1,
accuracy_order=6, xmin=xmin, xmax=xmax, N=10^3)
Di_SBP = dissipation_operator(MattssonSvärdNordström2004(), D_SBP)
Di_sparse = sparse(Di_SBP)
Di_banded = BandedMatrix(Di_SBP)
Di_full = Matrix(Di_SBP)
u = randn(eltype(D_SBP), size(D_SBP, 1)); du = similar(u);
@show Di_SBP * u ≈ Di_sparse * u ≈ Di_banded * u ≈ Di_full * u
function doit(D, text, du, u)
println(text)
sleep(0.1)
show(stdout, MIME"text/plain"(), @benchmark mul!($du, $D, $u))
println()
end
doit (generic function with 1 method)
At first, let us benchmark the derivative and dissipation operators implemented in SummationByPartsOperators.jl.
doit(D_SBP, "D_SBP:", du, u)
doit(Di_SBP, "Di_SBP:", du, u)
D_SBP:
BenchmarkTools.Trial: 10000 samples with 202 evaluations.
Range (min … max): 387.802 ns … 672.540 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 392.262 ns ┊ GC (median): 0.00%
Time (mean ± σ): 395.968 ns ± 12.501 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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388 ns Histogram: log(frequency) by time 438 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
Di_SBP:
BenchmarkTools.Trial: 10000 samples with 10 evaluations.
Range (min … max): 1.016 μs … 2.970 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 1.027 μs ┊ GC (median): 0.00%
Time (mean ± σ): 1.036 μs ± 82.576 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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1.02 μs Histogram: frequency by time 1.75 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Next, we compare the results to sparse matrix representations. It will not come as a surprise that these are again much (around an order of magnitude) slower.
doit(Di_sparse, "Di_sparse:", du, u)
doit(Di_banded, "Di_banded:", du, u)
Di_sparse:
BenchmarkTools.Trial: 10000 samples with 6 evaluations.
Range (min … max): 5.240 μs … 9.509 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 5.323 μs ┊ GC (median): 0.00%
Time (mean ± σ): 5.372 μs ± 256.093 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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5.24 μs Histogram: log(frequency) by time 6.64 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Di_banded:
BenchmarkTools.Trial: 10000 samples with 5 evaluations.
Range (min … max): 6.173 μs … 14.791 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 6.823 μs ┊ GC (median): 0.00%
Time (mean ± σ): 6.692 μs ± 684.690 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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6.17 μs Histogram: log(frequency) by time 10.6 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Finally, let's benchmark the same computation if a full (dense) matrix is used to represent the derivative operator. This is obviously a bad idea but 🤷
doit(Di_full, "Di_full:", du, u)
Di_full:
BenchmarkTools.Trial: 10000 samples with 1 evaluation.
Range (min … max): 133.709 μs … 602.513 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 135.783 μs ┊ GC (median): 0.00%
Time (mean ± σ): 138.902 μs ± 12.878 μs ┊ GC (mean ± σ): 0.00% ± 0.00%
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134 μs Histogram: log(frequency) by time 182 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
These results were obtained using the following versions.
using InteractiveUtils
versioninfo()
using Pkg
Pkg.status(["SummationByPartsOperators", "BandedMatrices"],
mode=PKGMODE_MANIFEST)
Julia Version 1.6.7
Commit 3b76b25b64 (2022-07-19 15:11 UTC)
Platform Info:
OS: Linux (x86_64-pc-linux-gnu)
CPU: AMD EPYC 7763 64-Core Processor
WORD_SIZE: 64
LIBM: libopenlibm
LLVM: libLLVM-11.0.1 (ORCJIT, generic)
Environment:
JULIA_PKG_SERVER_REGISTRY_PREFERENCE = eager
Status `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl/docs/Manifest.toml`
[aae01518] BandedMatrices v0.17.18
[9f78cca6] SummationByPartsOperators v0.5.70 `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl`
Structure-of-Arrays (SoA) and Array-of-Structures (AoS)
SummationByPartsOperators.jl tries to provide efficient support of
StaticVector
s from StaticArrays.jl- StructArrays.jl
To demonstrate this, let us set up some benchmark code.
using BenchmarkTools
using StaticArrays, StructArrays
using LinearAlgebra, SparseArrays
using SummationByPartsOperators
BLAS.set_num_threads(1) # make sure that BLAS is serial to be fair
struct Vec5{T} <: FieldVector{5,T}
x1::T
x2::T
x3::T
x4::T
x5::T
end
# Apply `mul!` to each component of a plain array of structures one after another
function mul_aos!(du, D, u, args...)
for i in 1:size(du, 1)
mul!(view(du, i, :), D, view(u, i, :), args...)
end
end
T = Float64
xmin, xmax = T(0), T(1)
D_SBP = derivative_operator(MattssonNordström2004(), derivative_order=1,
accuracy_order=4, xmin=xmin, xmax=xmax, N=101)
D_sparse = sparse(D_SBP)
D_full = Matrix(D_SBP)
101×101 Matrix{Float64}:
-141.176 173.529 -23.5294 … 0.0 0.0 0.0
-50.0 0.0 50.0 0.0 0.0 0.0
9.30233 -68.6047 0.0 0.0 0.0 0.0
3.06122 0.0 -60.2041 0.0 0.0 0.0
0.0 0.0 8.33333 0.0 0.0 0.0
0.0 0.0 0.0 … 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0
⋮ ⋱ ⋮
0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 … 0.0 0.0 0.0
0.0 0.0 0.0 -8.33333 0.0 0.0
0.0 0.0 0.0 60.2041 0.0 -3.06122
0.0 0.0 0.0 0.0 68.6047 -9.30233
0.0 0.0 0.0 -50.0 0.0 50.0
0.0 0.0 0.0 … 23.5294 -173.529 141.176
At first, we benchmark the application of the operators implemented in SummationByPartsOperators.jl and their representations as sparse and dense matrices in the scalar case. As before, the sparse matrix representation is around an order of magnitude slower and the dense matrix representation is far off.
println("Scalar case")
u = randn(T, size(D_SBP, 1)); du = similar(u)
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($du, $D_SBP, $u))
println("\nD_sparse")
show(stdout, MIME"text/plain"(), @benchmark mul!($du, $D_sparse, $u))
println("\nD_full")
show(stdout, MIME"text/plain"(), @benchmark mul!($du, $D_full, $u))
Scalar case
D_SBP
BenchmarkTools.Trial: 10000 samples with 989 evaluations.
Range (min … max): 46.052 ns … 75.257 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 46.802 ns ┊ GC (median): 0.00%
Time (mean ± σ): 47.269 ns ± 1.925 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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46.1 ns Histogram: frequency by time 55.2 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 232 evaluations.
Range (min … max): 318.655 ns … 513.112 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 328.586 ns ┊ GC (median): 0.00%
Time (mean ± σ): 332.282 ns ± 11.530 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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319 ns Histogram: frequency by time 370 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 10 evaluations.
Range (min … max): 1.711 μs … 4.043 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 1.724 μs ┊ GC (median): 0.00%
Time (mean ± σ): 1.745 μs ± 126.880 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
██▂ ▂
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1.71 μs Histogram: log(frequency) by time 2.52 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Next, we use a plain array of structures (AoS) in the form of a two-dimensional array and our custom mul_aos!
implementation that loops over each component, using mul!
on view
s. Here, the differences between the timings are less pronounced.
println("Plain Array of Structures")
u_aos_plain = randn(T, 5, size(D_SBP, 1)); du_aos_plain = similar(u_aos_plain)
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul_aos!($du_aos_plain, $D_SBP, $u_aos_plain))
println("\nD_sparse")
show(stdout, MIME"text/plain"(), @benchmark mul_aos!($du_aos_plain, $D_sparse, $u_aos_plain))
println("\nD_full")
show(stdout, MIME"text/plain"(), @benchmark mul_aos!($du_aos_plain, $D_full, $u_aos_plain))
Plain Array of Structures
D_SBP
BenchmarkTools.Trial: 10000 samples with 10 evaluations.
Range (min … max): 1.306 μs … 3.338 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 1.314 μs ┊ GC (median): 0.00%
Time (mean ± σ): 1.328 μs ± 101.681 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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1.31 μs Histogram: log(frequency) by time 2.06 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 9 evaluations.
Range (min … max): 2.354 μs … 6.020 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 2.410 μs ┊ GC (median): 0.00%
Time (mean ± σ): 2.438 μs ± 174.225 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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2.35 μs Histogram: log(frequency) by time 3.27 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 3 evaluations.
Range (min … max): 8.980 μs … 21.467 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 9.040 μs ┊ GC (median): 0.00%
Time (mean ± σ): 9.138 μs ± 540.497 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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8.98 μs Histogram: log(frequency) by time 11.8 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Now, we use an array of structures (AoS) based on reinterpret
and standard mul!
. This is much more efficient for the implementation in SummationByPartsOperators.jl. In Julia v1.6, this is also more efficient for sparse matrices but less efficient for dense matrices (compared to the plain AoS approach with mul_aos!
above).
println("Array of Structures (reinterpreted array)")
u_aos_r = reinterpret(reshape, Vec5{T}, u_aos_plain); du_aos_r = similar(u_aos_r)
@show D_SBP * u_aos_r ≈ D_sparse * u_aos_r ≈ D_full * u_aos_r
mul!(du_aos_r, D_SBP, u_aos_r)
@show reinterpret(reshape, T, du_aos_r) ≈ du_aos_plain
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($du_aos_r, $D_SBP, $u_aos_r))
println("\nD_sparse")
show(stdout, MIME"text/plain"(), @benchmark mul!($du_aos_r, $D_sparse, $u_aos_r))
println("\nD_full")
show(stdout, MIME"text/plain"(), @benchmark mul!($du_aos_r, $D_full, $u_aos_r))
Array of Structures (reinterpreted array)
D_SBP * u_aos_r ≈ D_sparse * u_aos_r ≈ D_full * u_aos_r = true
reinterpret(reshape, T, du_aos_r) ≈ du_aos_plain = true
D_SBP
BenchmarkTools.Trial: 10000 samples with 570 evaluations.
Range (min … max): 205.558 ns … 306.765 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 208.089 ns ┊ GC (median): 0.00%
Time (mean ± σ): 209.877 ns ± 4.802 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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206 ns Histogram: frequency by time 224 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 187 evaluations.
Range (min … max): 548.080 ns … 823.674 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 560.567 ns ┊ GC (median): 0.00%
Time (mean ± σ): 565.598 ns ± 16.284 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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548 ns Histogram: frequency by time 613 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 4 evaluations.
Range (min … max): 7.301 μs … 15.289 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 7.354 μs ┊ GC (median): 0.00%
Time (mean ± σ): 7.434 μs ± 441.612 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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7.3 μs Histogram: log(frequency) by time 9.38 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Next, we still use an array of structures (AoS), but copy the data into a plain Array
instead of using the reinterpret
ed versions. There is no significant difference to the previous version in this case.
println("Array of Structures")
u_aos = Array(u_aos_r); du_aos = similar(u_aos)
@show D_SBP * u_aos ≈ D_sparse * u_aos ≈ D_full * u_aos
mul!(du_aos, D_SBP, u_aos)
@show du_aos ≈ du_aos_r
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($du_aos, $D_SBP, $u_aos))
println("\nD_sparse")
show(stdout, MIME"text/plain"(), @benchmark mul!($du_aos, $D_sparse, $u_aos))
println("\nD_full")
show(stdout, MIME"text/plain"(), @benchmark mul!($du_aos, $D_full, $u_aos))
Array of Structures
D_SBP * u_aos ≈ D_sparse * u_aos ≈ D_full * u_aos = true
du_aos ≈ du_aos_r = true
D_SBP
BenchmarkTools.Trial: 10000 samples with 565 evaluations.
Range (min … max): 206.650 ns … 290.506 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 210.942 ns ┊ GC (median): 0.00%
Time (mean ± σ): 213.077 ns ± 6.623 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▁▃▅▇█▇▆▄▂▁ ▂▃▄▄▂▁ ▂
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207 ns Histogram: log(frequency) by time 245 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 158 evaluations.
Range (min … max): 654.506 ns … 902.380 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 701.241 ns ┊ GC (median): 0.00%
Time (mean ± σ): 704.982 ns ± 20.929 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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655 ns Histogram: frequency by time 767 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 4 evaluations.
Range (min … max): 7.243 μs … 18.009 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 7.333 μs ┊ GC (median): 0.00%
Time (mean ± σ): 7.431 μs ± 578.957 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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7.24 μs Histogram: log(frequency) by time 9.44 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Finally, let's look at a structure of arrays (SoA). Interestingly, this is slower than the array of structures we used above. On Julia v1.6, the sparse matrix representation performs particularly bad in this case.
println("Structure of Arrays")
u_soa = StructArray(u_aos); du_soa = similar(u_soa)
@show D_SBP * u_soa ≈ D_sparse * u_soa ≈ D_full * u_soa
mul!(du_soa, D_SBP, u_soa)
@show du_soa ≈ du_aos
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($du_soa, $D_SBP, $u_soa))
println("\nD_sparse")
show(stdout, MIME"text/plain"(), @benchmark mul!($du_soa, $D_sparse, $u_soa))
println("\nD_full")
show(stdout, MIME"text/plain"(), @benchmark mul!($du_soa, $D_full, $u_soa))
Structure of Arrays
D_SBP * u_soa ≈ D_sparse * u_soa ≈ D_full * u_soa = true
du_soa ≈ du_aos = true
D_SBP
BenchmarkTools.Trial: 10000 samples with 446 evaluations.
Range (min … max): 230.092 ns … 307.166 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 232.496 ns ┊ GC (median): 0.00%
Time (mean ± σ): 234.547 ns ± 6.354 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▄██▆▂
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230 ns Histogram: frequency by time 255 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 1 evaluation.
Range (min … max): 213.808 μs … 7.925 ms ┊ GC (min … max): 0.00% … 95.59%
Time (median): 223.175 μs ┊ GC (median): 0.00%
Time (mean ± σ): 280.432 μs ± 454.783 μs ┊ GC (mean ± σ): 10.35% ± 6.19%
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214 μs Histogram: log(frequency) by time 412 μs <
Memory estimate: 328.25 KiB, allocs estimate: 10504.
D_full
BenchmarkTools.Trial: 10000 samples with 1 evaluation.
Range (min … max): 174.706 μs … 7.530 ms ┊ GC (min … max): 0.00% … 96.22%
Time (median): 182.841 μs ┊ GC (median): 0.00%
Time (mean ± σ): 236.956 μs ± 451.834 μs ┊ GC (mean ± σ): 12.19% ± 6.22%
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175 μs Histogram: frequency by time 328 μs <
Memory estimate: 328.25 KiB, allocs estimate: 10504.
These results were obtained using the following versions.
using InteractiveUtils
versioninfo()
using Pkg
Pkg.status(["SummationByPartsOperators", "StaticArrays", "StructArrays"],
mode=PKGMODE_MANIFEST)
Julia Version 1.6.7
Commit 3b76b25b64 (2022-07-19 15:11 UTC)
Platform Info:
OS: Linux (x86_64-pc-linux-gnu)
CPU: AMD EPYC 7763 64-Core Processor
WORD_SIZE: 64
LIBM: libopenlibm
LLVM: libLLVM-11.0.1 (ORCJIT, generic)
Environment:
JULIA_PKG_SERVER_REGISTRY_PREFERENCE = eager
Status `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl/docs/Manifest.toml`
[90137ffa] StaticArrays v1.9.7
[09ab397b] StructArrays v0.6.18
[9f78cca6] SummationByPartsOperators v0.5.70 `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl`