Compiled HPL (High-Performance Linpack Benchmark) for Linux on ARM64 (AARCH64)
HPL is used by top500.org to rank the world's fastest supercomputers by FLOPs (floating-points operations per second). It can also be used to test the stability of your CPU, CPU frequency throttling (you either observe the actual frequency or determine it by lower FLOPs), CPU cache, RAM, and the power supply since HPL is quite demanding and also performs the result verification (see PASSED/FAILED below). On the other hand, HPL is not ideal for testing the maximum temperature. The CPU gets quite hot during the calculation phase, but cools down during the verification phase.
The best FLOPs for ARM64 (probably for other archs as well) are usually obtained using OpenBLAS library. However, it is advisable not to use the library compiled by your distribution. For better results, compile it yourself or use the provided binaries. Alternatively, one can utilize BLIS libraries, ARM Performance Libraries, or any other BLAS implementation.
wget https://github.com/xianyi/OpenBLAS/archive/refs/tags/v0.3.25.tar.gz
tar xvf v0.3.25.tar.gz
cd OpenBLAS-0.3.25
export NO_SHARED=1
export TARGET=CORTEXA53
NO_FORTRAN=1 NUM_THREADS=8 USE_OPENMP=1 make -j$(nproc)
make PREFIX=${HOME}/openblas install
The possible TARGETs are listed in file the TargetList.txt. For our purpose, the relevant options include: ARMV8, CORTEXA53, CORTEXA55, CORTEXA57, CORTEXA72, CORTEXA73, and CORTEXX1 (good for CORTEX-A76, A77, and A78?). Not setting TARGET will result in an automatic detection.
We no longer need the shared libraries (so) as we link OpenBLAS statically to the final xhpl binary, the option NO_SHARED=1 takes care of this.
It is also posible to use DYNAMIC_ARCH=1 to compile all the supported CPUs into one library. Specify the maximum number of threads by using NUM_THREADS=8.
wget https://github.com/xianyi/OpenBLAS/archive/refs/tags/v0.3.25.tar.gz
tar xvf v0.3.25.tar.gz
cd OpenBLAS-0.3.25
export NO_SHARED=1
export TARGET=ARMV8
export DYNAMIC_ARCH=1
NO_FORTRAN=1 NUM_THREADS=8 USE_OPENMP=1 make -j$(nproc)
make PREFIX=${HOME}/openblas install
wget https://github.com/flame/blis/archive/refs/tags/0.9.0.tar.gz
tar xvf 0.9.0.tar.gz
cd blis-0.9.0
./configure -p ${HOME}/blis --disable-shared -t openmp auto
make -j${nproc}
make check
make install
ln -s ${HOME}/blis/lib/libblis.a ${HOME}/blis/lib/libopenblas.a
The auto option should compile the right library, but the detection algorithm might be inaccurate. You can view all the available possibilities by using the command ls config. For ARM64 there are cortexa53, cortexa57, firestorm (Apple A14, M1), thunderx2 (Neoverse N1), and generic. Recently, there is also support for configuration families. In that case, use arm64, and all posibilities are compiled, with the correct one chosen at runtime. However, the detection might still be incorrect. Select the right library and link it to the HPL.
sudo apt install -y libopenmpi-dev
wget https://www.netlib.org/benchmark/hpl/hpl-2.3.tar.gz
tar xvf hpl-2.3.tar.gz
cd hpl-2.3
LDFLAGS=-L${HOME}/openblas/lib CFLAGS="-pthread -fopenmp" ./configure
make -j$(nproc)
LDFLAGS=-L${HOME}/blis/lib CFLAGS="-pthread -fopenmp" ./configure
make -j$(nproc)
The resulting binary is hpl-2.3/testing/xhpl
It turns out that the OpenBLAS binary for CORTEX-A53 and CORTEX-A55 are the same. And CORTEX-A57 and CORTEX-A72 are identical as well. This is because HPL utilizes only a limited set of functions (dgemm, daxpy, dcopy, dgemv, dger, dscal, dswap, dtrsm, dtrsv, and idamax) from OpenBLAS, and these functions are identical for these specified targets.
As mentioned earlier, the CORTEX-A53 and CORTEX-A55 are the same, and similarly, the CORTEX-A57 and CORTEX-A72 are identical.
You need an openmpi library, even if you intend to run it in OpenMP mode, which will automatically utilize all available cores. If you wish to use MPI, you can modify the values of P and Q in the HPL.dat file.
sudo apt install openmpi-bin
Additionally, you need to create a HPL.dat text file, which may look something like this:
HPLinpack benchmark input file
Innovative Computing Laboratory, University of Tennessee
HPL.out output file name (if any)
6 device out (6=stdout,7=stderr,file)
1 # of problems sizes (N)
28000 Ns
20 # of NBs
96 104 112 120 128 136 144 152 160 168 176 184 192 200 208 216 224 232 240 248 NBs
0 PMAP process mapping (0=Row-,1=Column-major)
1 # of process grids (P x Q)
1 Ps
1 Qs
16.0 threshold
1 # of panel fact
1 PFACTs (0=left, 1=Crout, 2=Right)
1 # of recursive stopping criterium
4 NBMINs (>= 1)
1 # of panels in recursion
2 NDIVs
1 # of recursive panel fact.
2 RFACTs (0=left, 1=Crout, 2=Right)
1 # of broadcast
2 BCASTs (0=1rg,1=1rM,2=2rg,3=2rM,4=Lng,5=LnM)
1 # of lookahead depth
0 DEPTHs (>=0)
2 SWAP (0=bin-exch,1=long,2=mix)
8 swapping threshold
0 L1 in (0=transposed,1=no-transposed) form
0 U in (0=transposed,1=no-transposed) form
1 Equilibration (0=no,1=yes)
8 memory alignment in double (> 0)
The parameter Ns is the size of the square matrix Ns × Ns, and the memory consumption is directly proportional to Ns^2. Ns=20000 needs around 4GB RAM, for 8GB use 28000, for 2GB use 14000, and for 1GB 10000. Try to use all the RAM as it improves the FLOPs, but you should avoid swapping as it drastically decreased FLOPs.
| RAM (GB) | optimal Ns |
|---|---|
| 0.5 | 7000 |
| 1 | 10000 |
| 2 | 14000 |
| 4 | 20000 |
| 8 | 28000 |
| 16 | 40000 |
| 32 | 57000 |
There is a formula to calculate the N.
The parameters NB determines the size of the blocks used for calculation. Its optimization is a bit of guesswork. It probably depends a lot on CPU caches and RAM speed. So in the example file you have 12 different NBs. The HPL will run for all of them and you can choose the one with the highest FLOPs.
Then just run xhpl. Sample output:
HPLinpack 2.3 -- High-Performance Linpack benchmark -- December 2, 2018
Written by A. Petitet and R. Clint Whaley, Innovative Computing Laboratory, UTK
Modified by Piotr Luszczek, Innovative Computing Laboratory, UTK
Modified by Julien Langou, University of Colorado Denver
================================================================================
An explanation of the input/output parameters follows:
T/V : Wall time / encoded variant.
N : The order of the coefficient matrix A.
NB : The partitioning blocking factor.
P : The number of process rows.
Q : The number of process columns.
Time : Time in seconds to solve the linear system.
Gflops : Rate of execution for solving the linear system.
The following parameter values will be used:
N : 20000
NB : 32 48 64 80 96 112 128 144
160 176 192 208
PMAP : Row-major process mapping
P : 1
Q : 1
PFACT : Crout
NBMIN : 4
NDIV : 2
RFACT : Right
BCAST : 1ring
DEPTH : 0
SWAP : Mix (threshold = 8)
L1 : transposed form
U : transposed form
EQUIL : yes
ALIGN : 8 double precision words
--------------------------------------------------------------------------------
- The matrix A is randomly generated for each test.
- The following scaled residual check will be computed:
||Ax-b||_oo / ( eps * ( || x ||_oo * || A ||_oo + || b ||_oo ) * N )
- The relative machine precision (eps) is taken to be 1.110223e-16
- Computational tests pass if scaled residuals are less than 16.0
================================================================================
T/V N NB P Q Time Gflops
--------------------------------------------------------------------------------
WR00R2C4 20000 32 1 1 522.34 1.0212e+01
HPL_pdgesv() start time Fri Aug 26 12:45:04 2022
HPL_pdgesv() end time Fri Aug 26 12:53:47 2022
--------------------------------------------------------------------------------
||Ax-b||_oo/(eps*(||A||_oo*||x||_oo+||b||_oo)*N)= 4.40719904e-03 ...... PASSED
...
Sometimes instead of PASSED you can see FAILED, which means that the residual sums are higher than expected and your CPU calculated the result wrongly. This can be due to too high CPU frequency, not enough CPU voltage, or due to overheating. Often the computer may also crash or restart. Which is also a sign of instability.
The Huge Pages can improve your FLOPs by approximately 10%. The easiest method is to enable the Transparent Huge Pages (THP) if your kernel supports them. For instance, the official Raspberry Pi kernel has THP disabled for some reason.
echo always | sudo tee /sys/kernel/mm/transparent_hugepage/enabled
echo always | sudo tee /sys/kernel/mm/transparent_hugepage/defrag
echo 1 | sudo tee /sys/kernel/mm/transparent_hugepage/use_zero_page
The best FLOPs of 20 runs or more
| SBC | cpu | GHz | cores | RAM GB | Ns | optimal NB | binary | GFLOPs | THP | FLOPs/cycle/core | temp ℃ | power W | idle ℃ | idle W |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Raspberry3B+ | A53 | 1.4 | 4 | 1 | no | |||||||||
| 〃 | 〃 | 〃 | 1 | 〃 | yes | 〃 | 〃 | |||||||
| Raspberry4 | A72 | 1.8 | 4 | 8 | 28000 | 168 | a57 BLIS | 18.44 | yes | 2.56 | 62 | 10 | 37 | 4 |
| 〃 | 〃 | 〃 | 1 | 〃 | 28080 | 240 | 〃 | 5.82 | yes | 3.23 | 50 | 6 | 〃 | 〃 |
| Odroid-HC4 | A55 | 1.8 | 4 | 4 | 18000 | 144 | a53/55 | 14.46 | yes | 2.01 | 63 | |||
| 〃 | 〃 | 〃 | 1 | 〃 | yes | 〃 | 〃 | |||||||
| Odroid-M1 | A55 | 1.992 | 4 | 8 | 28000 | 144 | a53/55 | 15.08 | yes | 1.89 | 51 | 10 | 26 | 3 |
| 〃 | 〃 | 〃 | 1 | 〃 | 〃 | yes | 31 | 5 | 〃 | 〃 | ||||
| VIM 3 | A73 | 2.4 | 4 | 4 | 20000 | 184 | a57 BLIS | 17.6 | yes | 1.83 | ||||
| 〃 | 〃 | 〃 | 1 | 〃 | 20000 | 200 | a57 BLIS | 5.49 | yes | 2.04 | ||||
| VIM 3 LITTLE | A53 | 2.016 | 2 | 4 | yes | 〃 | 〃 | |||||||
| 〃 | 〃 | 〃 | 1 | 〃 | yes | 〃 | 〃 | |||||||
| OrangePi4 big | A72 | 1.8 | 2 | 4 | 20160 | 252 | OpenBLAS | 10.84 | yes | 3.01 | 29 | 4 | ||
| 〃 | 〃 | 〃 | 1 | 〃 | 20088 | 124 | OpenBLAS | 5.83 | yes | 3.24 | 〃 | 〃 | ||
| OrangePi4 LITTLE | A53 | 1.416 | 4 | 4 | 20064 | 176 | OpenBLAS | 11.41 | yes | 2.01 | 〃 | 〃 | ||
| 〃 | 〃 | 〃 | 1 | 〃 | 20088 | 248 | OpenBLAS | 3.39 | yes | 2.40 | 〃 | 〃 | ||
| Orange Pi 5 Plus | A76/A55 | 1.8 | 4/4 | 16 | 40000 | 232 | BLIS | 25.6 | 1.77 | |||||
| ^ RK3588 | 1.8 | 1 | 16 | 40000 | 96 | BLIS | 13.4 | 7.4 | ||||||
| Rock 5B big | A76 | 2.4 | 4 | 16 | 40040 | 220 | x1 OpenBLAS | 66.02 | yes | 6.88 | 62 | 15.9 | 34 | 2.3 |
| 〃 | 〃 | 〃 | 1 | 〃 | 40068 | 252 | 〃 | 17.21 | yes | 7.17 | 45 | 6.5 | 〃 | 〃 |
| Rock 5B LITTLE | A55 | 1.8 | 4 | 16 | 40000 | 120 | a53/55 OpenBLAS | 18.35 | yes | 2.55 | 36 | 〃 | 〃 | |
| 〃 | 〃 | 〃 | 1 | 〃 | 40096 | 224 | 〃 | 4.30 | no | 2.38 | 〃 | 〃 | ||
| Rock 5B | A76+A55 | 2.4, 1.8 | 4+4 | 16 | 32064, 20592 | 192, 176 | x1+a53/55 OpenBLAS | 60.96+15.79=76.75 | yes | - | 69 | 〃 | 〃 |
If you have additional results, I can include them in the table
According to Wikipedia Cortex-A53, A55, A57, A72, and A73 have 4 FLOPs/cycle/core. Cortex-A76, A77, and A78 have 8 FLOPs/cycle/core. So you can check that your ARM is reaching the correct FLOPs as it should.
It is more difficult to to handle big.LITTLE archs as HPL distributes the tasks equally, so the faster cores will have to wait for the slower ones. The easiest is to test separately the big and then the LITTLE cluster using taskset to target the needed cores. In this case we will get correct FLOPs for the clusters, but we will not maximally stress the CPU.
Uses the aluminium Armor Case with Dual Fan. To achieve 1.8GHz on newer boards, you need arm_boost=1 in /boot/config.txt. You can also specify hdmi_enable_4kp60=1, which increases the core frequency from 500MHz to 550MHz. The thermal throtling can be checked by vcgencmd get_throttled. The CPU temperature was under 62C and the thermal throttling was not reached.
Set the fan speed to the maximum by sudo systemctl stop fancontrol. Verify by running sensors, you should see around 4500RPM and /sys/class/hwmon/hwmon0/pwm1_enable should be 0. The CPU temperature is under 63C.
I used a USB 10cm fan pointed on the passive heatsink. Temperature was under 47C.
Without the fan with just the stock passive heatsink oriented upwards the results are lower and more scattered. It indicates that there was a thermal throttling, even though the /sys/devices/system/cpu/cpufreq/policy0/scaling_cur_freq still reports the default frequency of 1.992GHz. The GFLOPs with only the passive cooling were 13.23, so the frequency probably dropped to 1.748GHz. The CPU temperature reached 69C.
Stock VIM3 active cooling.
20000 184 2 2 301.54 1.7689e+01
20000 200 1 1 970.52 5.4959e+00
I used heatsinks on CPU and RAM with a case fan.
40000 232 2 4 1666.31 2.5607e+01
40000 96 1 1 3177.34 1.3429e+01
The Single Core (1P/1Q) performance is so nearly ideal that I think there is a lot still on the table. I pulled this from my initial run of 5 NBs. The RK3588 is a very enticing platform, with much higher inter-node communication potential. It already out-performs a 3-node cluster of 8G Pi 4s, and has 5x the networking throughput potential.
It has the same SoC as Orange Pi 5 (RK3588). With stock active fan and Rock's own software fan-control it reaches 75C and it looks like thermal throttling. However, the reported frequencies are still the same, they do not decrease (as with Odroid M1). It shows all the time 2352MHz for CPU 4 and 5, and 2304MHz for CPU 6 and 7. Additional cooling is necesary. The stock Radaxa kernel does not have THP support. Rock 5B is performing a slower than Orange Pi 5 with the same SoC. The difference is DMC (Dynamic Memory Interface), which automatically clocks RAM frequency down from 2112MHz to 528MHz (it saves about 0.5-0.6W when idle) and it is not activated in the Orange Pi kernel. To improve the benchmark, do either echo 25 >/sys/devices/platform/dmc/devfreq/dmc/upthreshold or echo performance | sudo tee /sys/class/devfreq/dmc/governor. The latter is reverted by echo dmc_ondemand | sudo tee /sys/class/devfreq/dmc/governor. The newer Radaxa kernel/image implements the firts workaround.