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 per sample.
Range (min … max): 28.345 ns … 63.435 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 29.453 ns ┊ GC (median): 0.00%
Time (mean ± σ): 30.022 ns ± 2.528 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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28.3 ns Histogram: log(frequency) by time 41.3 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 656 evaluations per sample.
Range (min … max): 187.684 ns … 357.271 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 200.055 ns ┊ GC (median): 0.00%
Time (mean ± σ): 199.929 ns ± 6.474 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▂██▅▁
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188 ns Histogram: frequency by time 219 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 115 evaluations per sample.
Range (min … max): 761.078 ns … 73.696 μs ┊ GC (min … max): 0.00% … 98.16%
Time (median): 780.330 ns ┊ GC (median): 0.00%
Time (mean ± σ): 841.573 ns ± 1.696 μs ┊ GC (mean ± σ): 4.90% ± 2.41%
▂▇██▆▅▄▃▂▂▃▂▃▃▃▃▄▄▃▁▁ ▂
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761 ns Histogram: log(frequency) by time 1.1 μs <
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 v0.5.75 `~/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 203 evaluations per sample.
Range (min … max): 382.394 ns … 680.739 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 386.788 ns ┊ GC (median): 0.00%
Time (mean ± σ): 390.128 ns ± 12.330 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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382 ns Histogram: frequency by time 428 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 per sample.
Range (min … max): 4.539 μs … 10.710 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 4.581 μs ┊ GC (median): 0.00%
Time (mean ± σ): 4.628 μs ± 257.673 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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4.54 μs Histogram: log(frequency) by time 5.68 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 per sample.
Range (min … max): 6.638 μs … 15.812 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 6.658 μs ┊ GC (median): 0.00%
Time (mean ± σ): 6.744 μs ± 476.318 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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6.64 μs Histogram: log(frequency) by time 8.66 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 v0.5.75 `~/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 203 evaluations per sample.
Range (min … max): 382.887 ns … 790.310 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 387.872 ns ┊ GC (median): 0.00%
Time (mean ± σ): 392.638 ns ± 16.771 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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383 ns Histogram: log(frequency) by time 464 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
Di_SBP:
BenchmarkTools.Trial: 10000 samples with 10 evaluations per sample.
Range (min … max): 1.011 μs … 2.318 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 1.020 μs ┊ GC (median): 0.00%
Time (mean ± σ): 1.031 μs ± 82.354 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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1.01 μs Histogram: log(frequency) by time 1.72 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 per sample.
Range (min … max): 5.280 μs … 11.111 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 5.367 μs ┊ GC (median): 0.00%
Time (mean ± σ): 5.416 μs ± 260.219 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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5.28 μs Histogram: log(frequency) by time 6.62 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Di_banded:
BenchmarkTools.Trial: 10000 samples with 5 evaluations per sample.
Range (min … max): 6.184 μs … 17.006 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 6.210 μs ┊ GC (median): 0.00%
Time (mean ± σ): 6.672 μs ± 783.935 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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6.18 μs Histogram: log(frequency) by time 10.7 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 per sample.
Range (min … max): 132.739 μs … 354.145 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 134.252 μs ┊ GC (median): 0.00%
Time (mean ± σ): 136.271 μs ± 6.375 μs ┊ GC (mean ± σ): 0.00% ± 0.00%
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133 μs Histogram: log(frequency) by time 159 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 v0.5.75 `~/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, $u))
Scalar case
D_SBP
BenchmarkTools.Trial: 10000 samples with 989 evaluations per sample.
Range (min … max): 46.113 ns … 93.989 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 46.771 ns ┊ GC (median): 0.00%
Time (mean ± σ): 47.569 ns ± 3.150 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▇██▇▆▄▂ ▂▂▂▁▁ ▁ ▂
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46.1 ns Histogram: log(frequency) by time 62.3 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 235 evaluations per sample.
Range (min … max): 319.536 ns … 618.098 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 328.187 ns ┊ GC (median): 0.00%
Time (mean ± σ): 331.760 ns ± 11.915 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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320 ns Histogram: frequency by time 369 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 10 evaluations per sample.
Range (min … max): 1.677 μs … 4.461 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 1.687 μs ┊ GC (median): 0.00%
Time (mean ± σ): 1.709 μs ± 133.336 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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1.68 μs Histogram: log(frequency) by time 2.46 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Next, we use a plain array of structures (AoS) in the form of a two-dimensional array and our custom mul_aos!
implementation that loops over each component, using mul!
on view
s. Here, the differences between the timings are less pronounced.
println("Plain Array of Structures")
u_aos_plain = randn(T, 5, size(D_SBP, 1)); du_aos_plain = similar(u_aos_plain)
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul_aos!($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, $u_aos_plain))
Plain Array of Structures
D_SBP
BenchmarkTools.Trial: 10000 samples with 10 evaluations per sample.
Range (min … max): 1.325 μs … 2.834 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 1.335 μs ┊ GC (median): 0.00%
Time (mean ± σ): 1.346 μs ± 90.880 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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1.32 μs Histogram: frequency by time 2.06 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 9 evaluations per sample.
Range (min … max): 2.339 μs … 5.801 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 2.406 μs ┊ GC (median): 0.00%
Time (mean ± σ): 2.430 μs ± 149.867 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▃▆██▇▆▃▁ ▁ ▂
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2.34 μs Histogram: log(frequency) by time 3.25 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 3 evaluations per sample.
Range (min … max): 8.747 μs … 20.752 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 8.810 μs ┊ GC (median): 0.00%
Time (mean ± σ): 8.906 μs ± 527.785 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▆█▆ ▁
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8.75 μs Histogram: log(frequency) by time 11.3 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Now, we use an array of structures (AoS) based on reinterpret
and standard mul!
. This is much more efficient for the implementation in SummationByPartsOperators.jl. In Julia v1.6, this is also more efficient for sparse matrices but less efficient for dense matrices (compared to the plain AoS approach with mul_aos!
above).
println("Array of Structures (reinterpreted array)")
u_aos_r = reinterpret(reshape, Vec5{T}, u_aos_plain); du_aos_r = similar(u_aos_r)
@show D_SBP * u_aos_r ≈ D_sparse * u_aos_r ≈ D_full * u_aos_r
mul!(du_aos_r, D_SBP, u_aos_r)
@show reinterpret(reshape, T, du_aos_r) ≈ du_aos_plain
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($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, $u_aos_r))
Array of Structures (reinterpreted array)
D_SBP * u_aos_r ≈ D_sparse * u_aos_r ≈ D_full * u_aos_r = true
reinterpret(reshape, T, du_aos_r) ≈ du_aos_plain = true
D_SBP
BenchmarkTools.Trial: 10000 samples with 550 evaluations per sample.
Range (min … max): 208.518 ns … 290.236 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 211.251 ns ┊ GC (median): 0.00%
Time (mean ± σ): 213.112 ns ± 5.431 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▂▆█▄
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209 ns Histogram: frequency by time 230 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 189 evaluations per sample.
Range (min … max): 537.413 ns … 913.460 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 546.370 ns ┊ GC (median): 0.00%
Time (mean ± σ): 551.372 ns ± 16.449 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▅██▅▃
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537 ns Histogram: frequency by time 598 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 4 evaluations per sample.
Range (min … max): 7.298 μs … 17.753 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 7.359 μs ┊ GC (median): 0.00%
Time (mean ± σ): 7.551 μs ± 837.267 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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7.3 μs Histogram: log(frequency) by time 12.6 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Next, we still use an array of structures (AoS), but copy the data into a plain Array
instead of using the reinterpret
ed versions. There is no significant difference to the previous version in this case.
println("Array of Structures")
u_aos = Array(u_aos_r); du_aos = similar(u_aos)
@show D_SBP * u_aos ≈ D_sparse * u_aos ≈ D_full * u_aos
mul!(du_aos, D_SBP, u_aos)
@show du_aos ≈ du_aos_r
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($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, $u_aos))
Array of Structures
D_SBP * u_aos ≈ D_sparse * u_aos ≈ D_full * u_aos = true
du_aos ≈ du_aos_r = true
D_SBP
BenchmarkTools.Trial: 10000 samples with 535 evaluations per sample.
Range (min … max): 211.312 ns … 293.297 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 215.228 ns ┊ GC (median): 0.00%
Time (mean ± σ): 217.868 ns ± 8.096 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▁▄▆██▆▄▁▁▁ ▂▄▄▃▁ ▂
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211 ns Histogram: log(frequency) by time 257 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 179 evaluations per sample.
Range (min … max): 590.492 ns … 1.070 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 603.034 ns ┊ GC (median): 0.00%
Time (mean ± σ): 611.317 ns ± 34.349 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▅██▅▃▁ ▁▄▄▂ ▂
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590 ns Histogram: log(frequency) by time 834 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 4 evaluations per sample.
Range (min … max): 7.381 μs … 23.820 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 7.444 μs ┊ GC (median): 0.00%
Time (mean ± σ): 7.540 μs ± 652.149 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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7.38 μs Histogram: log(frequency) by time 9.36 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Finally, let's look at a structure of arrays (SoA). Interestingly, this is slower than the array of structures we used above. On Julia v1.6, the sparse matrix representation performs particularly bad in this case.
println("Structure of Arrays")
u_soa = StructArray(u_aos); du_soa = similar(u_soa)
@show D_SBP * u_soa ≈ D_sparse * u_soa ≈ D_full * u_soa
mul!(du_soa, D_SBP, u_soa)
@show du_soa ≈ du_aos
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($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 434 evaluations per sample.
Range (min … max): 232.901 ns … 409.917 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 235.005 ns ┊ GC (median): 0.00%
Time (mean ± σ): 237.994 ns ± 10.527 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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233 ns Histogram: log(frequency) by time 298 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 1 evaluation per sample.
Range (min … max): 212.800 μs … 14.505 ms ┊ GC (min … max): 0.00% … 51.22%
Time (median): 221.361 μs ┊ GC (median): 0.00%
Time (mean ± σ): 274.235 μs ± 477.409 μs ┊ GC (mean ± σ): 10.73% ± 6.16%
▂▅█▄▅▅▃▂▁▁▁ ▂▄▃▂▃▂ ▂
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213 μs Histogram: log(frequency) by time 415 μs <
Memory estimate: 328.25 KiB, allocs estimate: 10504.
D_full
BenchmarkTools.Trial: 10000 samples with 1 evaluation per sample.
Range (min … max): 176.882 μs … 17.087 ms ┊ GC (min … max): 0.00% … 39.59%
Time (median): 186.120 μs ┊ GC (median): 0.00%
Time (mean ± σ): 234.939 μs ± 464.242 μs ┊ GC (mean ± σ): 12.02% ± 6.21%
▃▅▅█▅▃▅▅▂▁ ▂▃▃▃▂▂▂▁ ▂
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177 μs Histogram: log(frequency) by time 330 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 v1.9.11
[09ab397b] StructArrays v0.6.18
[9f78cca6] SummationByPartsOperators v0.5.75 `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl`