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 994 evaluations per sample.
Range (min … max): 29.764 ns … 75.929 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 30.338 ns ┊ GC (median): 0.00%
Time (mean ± σ): 30.660 ns ± 1.577 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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29.8 ns Histogram: log(frequency) by time 38.1 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 595 evaluations per sample.
Range (min … max): 200.274 ns … 333.951 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 203.506 ns ┊ GC (median): 0.00%
Time (mean ± σ): 205.559 ns ± 5.901 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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200 ns Histogram: frequency by time 225 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 109 evaluations per sample.
Range (min … max): 768.404 ns … 68.071 μs ┊ GC (min … max): 0.00% … 98.06%
Time (median): 787.615 ns ┊ GC (median): 0.00%
Time (mean ± σ): 843.433 ns ± 1.609 μs ┊ GC (mean ± σ): 4.65% ± 2.41%
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768 ns Histogram: log(frequency) by time 956 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 v0.5.74 `~/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): 382.493 ns … 997.384 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 387.276 ns ┊ GC (median): 0.00%
Time (mean ± σ): 390.636 ns ± 12.952 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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382 ns Histogram: frequency by time 429 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): 4.769 μs … 10.375 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 4.819 μs ┊ GC (median): 0.00%
Time (mean ± σ): 4.868 μs ± 269.947 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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4.77 μs Histogram: log(frequency) by time 5.96 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): 6.640 μs … 13.768 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 6.658 μs ┊ GC (median): 0.00%
Time (mean ± σ): 6.721 μs ± 341.567 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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6.64 μs Histogram: log(frequency) by time 8.38 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 v0.5.74 `~/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 201 evaluations per sample.
Range (min … max): 394.970 ns … 579.040 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 402.144 ns ┊ GC (median): 0.00%
Time (mean ± σ): 406.550 ns ± 14.852 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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395 ns Histogram: frequency by time 471 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
Di_SBP:
BenchmarkTools.Trial: 10000 samples with 10 evaluations per sample.
Range (min … max): 1.283 μs … 3.800 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 1.352 μs ┊ GC (median): 0.00%
Time (mean ± σ): 1.368 μs ± 114.191 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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1.28 μs Histogram: log(frequency) by time 2.08 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): 5.235 μs … 13.462 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 5.265 μs ┊ GC (median): 0.00%
Time (mean ± σ): 5.318 μs ± 311.321 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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5.23 μs Histogram: log(frequency) by time 6.57 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Di_banded:
BenchmarkTools.Trial: 10000 samples with 5 evaluations per sample.
Range (min … max): 6.194 μs … 11.972 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 6.214 μs ┊ GC (median): 0.00%
Time (mean ± σ): 6.377 μs ± 445.425 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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6.19 μs Histogram: log(frequency) by time 8.34 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): 137.928 μs … 356.177 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 139.962 μs ┊ GC (median): 0.00%
Time (mean ± σ): 141.919 μs ± 5.570 μs ┊ GC (mean ± σ): 0.00% ± 0.00%
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138 μs Histogram: log(frequency) by time 162 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 v0.5.74 `~/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, $u))
Scalar case
D_SBP
BenchmarkTools.Trial: 10000 samples with 989 evaluations per sample.
Range (min … max): 45.343 ns … 90.199 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 45.971 ns ┊ GC (median): 0.00%
Time (mean ± σ): 46.417 ns ± 1.826 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
▂▆███▇▆▆▅▄▃▂▁ ▁▂▂▁▁▁ ▃
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45.3 ns Histogram: log(frequency) by time 53.9 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 228 evaluations per sample.
Range (min … max): 325.610 ns … 599.281 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 332.289 ns ┊ GC (median): 0.00%
Time (mean ± σ): 335.325 ns ± 11.724 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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326 ns Histogram: frequency by time 370 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 10 evaluations per sample.
Range (min … max): 1.715 μs … 6.071 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 1.726 μs ┊ GC (median): 0.00%
Time (mean ± σ): 1.871 μs ± 396.595 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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1.72 μs Histogram: log(frequency) by time 3.04 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Next, we use a plain array of structures (AoS) in the form of a two-dimensional array and our custom mul_aos!
implementation that loops over each component, using mul!
on view
s. Here, the differences between the timings are less pronounced.
println("Plain Array of Structures")
u_aos_plain = randn(T, 5, size(D_SBP, 1)); du_aos_plain = similar(u_aos_plain)
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul_aos!($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, $u_aos_plain))
Plain Array of Structures
D_SBP
BenchmarkTools.Trial: 10000 samples with 10 evaluations per sample.
Range (min … max): 1.298 μs … 3.242 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 1.307 μs ┊ GC (median): 0.00%
Time (mean ± σ): 1.321 μs ± 101.154 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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1.3 μs Histogram: log(frequency) by time 2.03 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 9 evaluations per sample.
Range (min … max): 2.351 μs … 5.509 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 2.404 μs ┊ GC (median): 0.00%
Time (mean ± σ): 2.430 μs ± 148.528 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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2.35 μs Histogram: log(frequency) by time 3.22 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 3 evaluations per sample.
Range (min … max): 8.937 μs … 15.863 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 8.993 μs ┊ GC (median): 0.00%
Time (mean ± σ): 9.091 μs ± 513.941 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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8.94 μs Histogram: log(frequency) by time 11.6 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Now, we use an array of structures (AoS) based on reinterpret
and standard mul!
. This is much more efficient for the implementation in SummationByPartsOperators.jl. In Julia v1.6, this is also more efficient for sparse matrices but less efficient for dense matrices (compared to the plain AoS approach with mul_aos!
above).
println("Array of Structures (reinterpreted array)")
u_aos_r = reinterpret(reshape, Vec5{T}, u_aos_plain); du_aos_r = similar(u_aos_r)
@show D_SBP * u_aos_r ≈ D_sparse * u_aos_r ≈ D_full * u_aos_r
mul!(du_aos_r, D_SBP, u_aos_r)
@show reinterpret(reshape, T, du_aos_r) ≈ du_aos_plain
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($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, $u_aos_r))
Array of Structures (reinterpreted array)
D_SBP * u_aos_r ≈ D_sparse * u_aos_r ≈ D_full * u_aos_r = true
reinterpret(reshape, T, du_aos_r) ≈ du_aos_plain = true
D_SBP
BenchmarkTools.Trial: 10000 samples with 570 evaluations per sample.
Range (min … max): 205.121 ns … 281.175 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 208.004 ns ┊ GC (median): 0.00%
Time (mean ± σ): 209.858 ns ± 5.289 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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205 ns Histogram: frequency by time 231 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 188 evaluations per sample.
Range (min … max): 537.926 ns … 788.819 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 552.473 ns ┊ GC (median): 0.00%
Time (mean ± σ): 557.286 ns ± 15.598 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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538 ns Histogram: frequency by time 612 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 4 evaluations per sample.
Range (min … max): 7.336 μs … 21.195 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 7.419 μs ┊ GC (median): 0.00%
Time (mean ± σ): 7.694 μs ± 1.404 μs ┊ GC (mean ± σ): 0.00% ± 0.00%
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7.34 μs Histogram: log(frequency) by time 16.6 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Next, we still use an array of structures (AoS), but copy the data into a plain Array
instead of using the reinterpret
ed versions. There is no significant difference to the previous version in this case.
println("Array of Structures")
u_aos = Array(u_aos_r); du_aos = similar(u_aos)
@show D_SBP * u_aos ≈ D_sparse * u_aos ≈ D_full * u_aos
mul!(du_aos, D_SBP, u_aos)
@show du_aos ≈ du_aos_r
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($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, $u_aos))
Array of Structures
D_SBP * u_aos ≈ D_sparse * u_aos ≈ D_full * u_aos = true
du_aos ≈ du_aos_r = true
D_SBP
BenchmarkTools.Trial: 10000 samples with 540 evaluations per sample.
Range (min … max): 210.152 ns … 285.589 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 214.048 ns ┊ GC (median): 0.00%
Time (mean ± σ): 216.073 ns ± 6.375 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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210 ns Histogram: frequency by time 246 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 182 evaluations per sample.
Range (min … max): 579.165 ns … 1.074 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 587.253 ns ┊ GC (median): 0.00%
Time (mean ± σ): 594.689 ns ± 31.993 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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579 ns Histogram: log(frequency) by time 708 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_full
BenchmarkTools.Trial: 10000 samples with 4 evaluations per sample.
Range (min … max): 7.414 μs … 19.557 μs ┊ GC (min … max): 0.00% … 0.00%
Time (median): 7.479 μs ┊ GC (median): 0.00%
Time (mean ± σ): 7.566 μs ± 521.487 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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7.41 μs Histogram: log(frequency) by time 9.43 μs <
Memory estimate: 0 bytes, allocs estimate: 0.
Finally, let's look at a structure of arrays (SoA). Interestingly, this is slower than the array of structures we used above. On Julia v1.6, the sparse matrix representation performs particularly bad in this case.
println("Structure of Arrays")
u_soa = StructArray(u_aos); du_soa = similar(u_soa)
@show D_SBP * u_soa ≈ D_sparse * u_soa ≈ D_full * u_soa
mul!(du_soa, D_SBP, u_soa)
@show du_soa ≈ du_aos
println("D_SBP")
show(stdout, MIME"text/plain"(), @benchmark mul!($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 496 evaluations per sample.
Range (min … max): 219.808 ns … 320.681 ns ┊ GC (min … max): 0.00% … 0.00%
Time (median): 222.292 ns ┊ GC (median): 0.00%
Time (mean ± σ): 224.024 ns ± 5.260 ns ┊ GC (mean ± σ): 0.00% ± 0.00%
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220 ns Histogram: frequency by time 239 ns <
Memory estimate: 0 bytes, allocs estimate: 0.
D_sparse
BenchmarkTools.Trial: 10000 samples with 1 evaluation per sample.
Range (min … max): 214.271 μs … 6.929 ms ┊ GC (min … max): 0.00% … 96.23%
Time (median): 224.229 μs ┊ GC (median): 0.00%
Time (mean ± σ): 271.484 μs ± 413.777 μs ┊ GC (mean ± σ): 9.85% ± 6.24%
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214 μs Histogram: frequency by time 376 μs <
Memory estimate: 328.25 KiB, allocs estimate: 10504.
D_full
BenchmarkTools.Trial: 10000 samples with 1 evaluation per sample.
Range (min … max): 174.617 μs … 6.726 ms ┊ GC (min … max): 0.00% … 96.77%
Time (median): 182.451 μs ┊ GC (median): 0.00%
Time (mean ± σ): 229.652 μs ± 416.134 μs ┊ GC (mean ± σ): 11.72% ± 6.28%
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175 μs Histogram: frequency by time 326 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 v1.9.10
[09ab397b] StructArrays v0.6.18
[9f78cca6] SummationByPartsOperators v0.5.74 `~/work/SummationByPartsOperators.jl/SummationByPartsOperators.jl`