Getting started

This section describes how to access both the command line and GUI of the testbed system front-end.

The testbed contains a front-end node riscv-login containing a 26-core Skylake Xeon Platinum CPU with 256GB RAM. The system drive is a 1TB SSD, and files are stored on 4TB of HDD RAID10 storage. Users can build their code on the front-end node, and they can be run on the RISC-V backend nodes (for details on submitting jobs, see here)

Command line access

The testbed system is only accessible via the hydra-vpn proxy host, and in the previous applying for access step you will have signed up for accounts on both hydra-vpn and riscv-login. To access the testbed you need to therefore first ssh to hydra-vpn via ssh username@hydra-vpn.epcc.ed.ac.uk , the first time that you access this you will need to use the password automatically allocated via the SAFE system (it can be retrieved via SAFE) and will be prompted to change this.

Once you have logged into hydra-vpn then you can access the testbed login node via ssh username@riscv-login . The workflow is illustrated below.

username@localhost:~$ ssh username@hydra-vpn.epcc.ed.ac.uk
[username@hydra-vpn ~]$ ssh username@riscv-login
[username@riscv-login ~]$

ADVICE:
It is possible to automate the proxy step by setting this up in your ssh .config file as a proxyjump

Desktop access

The lightweight XFCE desktop is installed on the front-end of the testbed system, which is especially useful for programming FPGAs as much of the tooling has a graphical component to it. The front-end is also running X2GO which tends to provide much better performance than vanilla X forwarding. Therefore we strongly suggest accessing the desktop via X2GO, with users just needing to install the client program which is available here.

Once the client is installed, create a new profile with settings matching those as illustrated below (assuming that you use the same username and password for both hydra-vpn and the riscv-login node.

NOTE:
Whilst it is possible to run the individual graphical tools directly via X2GO, we suggest doing this via the XFCE desktop environment as find that this provides a much better user experience.

RISC-V compilers and libraries

RISC-V compilers are available on the module environment:

bash-4.2$ module avail
...
------------------- /usr/local/share/riscv-compiler/modulefiles --------------------
   riscv32-linux/gnu-12.2       riscv64-linux/gnu-9.2-rvv     riscv64-linux/llvm-15.0
   riscv32-newlib/gnu-12.2      riscv64-linux/gnu-10.2-rvv    riscv64-linux/llvm-16.0 
   riscv64-linux/gnu-8.4-rvv    riscv64-linux/gnu-12.2        riscv64-newlib/gnu-12.2

The modules correspond to the following compiler configurations:

Module	Compiler	Version	Library	Bit	ISA	ABI	Prefix	Source
`riscv32-linux/gnu-12.2`	GNU	12.2.0	glibc (Linux)	32	RV32GC	ilp32d	`riscv32-unknown-linux-gnu-`	RISC-V GNU Toolchain
`riscv64-linux/gnu-12.2`	GNU	12.2.0	glibc (Linux)	64	RV64GC	lp64d	`riscv64-unknown-linux-gnu-`	RISC-V GNU Toolchain
`riscv32-newlib/gnu-12.2`	GNU	12.2.0	Newlib	32	RV32GC	ilp32d	`riscv32-unknown-elf-gnu-`	RISC-V GNU Toolchain
`riscv64-newlib/gnu-12.2`	GNU	12.2.0	Newlib	64	RV64GC	lp64d	`riscv64-unknown-elf-gnu-`	RISC-V GNU Toolchain
`riscv64-linux/gnu-8.4-rvv`	GNU	8.4	glibc (Linux)	64	RV64GC + V (0.7.1)	lp64d	`riscv64-unknown-linux-gnu-`	XuanTie GNU Toolchain 20210618
`riscv64-linux/gnu-9.2-rvv`	GNU	9.2	glibc (Linux)	64	RV64GC + V (0.7.1)	lp64d	`riscv64-unknown-linux-gnu-`	RISC-V GNU Toolchain: rvv-0.7.1
`riscv64-linux/gnu-10.2-rvv`	GNU	10.2	glibc (Linux)	64	RV64GC + V (0.7.1/1.0)	lp64d	`riscv64-unknown-linux-gnu-`	XuanTie GNU Toolchain V2.6.1 20220906
`riscv64-linux/llvm-15.0`	LLVM	15.0	glibc (Linux)	64	RV64GC + V (1.0)	lp64d	N/A	LLVM
`riscv64-linux/llvm-16.0`	LLVM	16.0	glibc (Linux)	64	RV64GC + V (1.0)	lp64d	N/A	LLVM

Once a compiler module is loaded (e.g. via module load riscv64-linux/gnu-12.2 or module load riscv64-linux/llvm-16.0), the compilers and associated tools can be called with the prefix above for GNU (e.g. riscv64-unknown-linux-gnu-gcc) and without prefix (e.g clang) for LLVM.

For details of what tools are included in the toolchains, see Toolchains & Cross-debugging. For more instructions on compiling with the V vector extension, see V vector extension.

Libraries

RISC-V libraries are also available in the module environment.

bash-4.2$ module avail
...
---------------------- /usr/local/share/riscv-software/modulefiles ----------------------
   fftw/3.3.10_gcc12.2_double/fftw-double
   fftw/3.3.10_gcc12.2_single/fftw-single
   hdf5/1.14.0_gcc12.2
   netcdf/4.x_gcc12.2
   openblas/0.3.21_C910V_gcc10.2
   openblas/0.3.21_riscv64_generic_gcc12.2 
   openmpi/4.1.4_gcc12.2
   petsc/3.18.4_debug
   petsc/3.18.4_release                    

To inspect the list of modules set in the user environment, run module list. More general details about the module environment can be found here.

Note: all libraries are compiled using riscv64-linux/gnu-12.2, except for openblas/0.3.21_C910V_gcc10.2 which has been compiled using XuanTie GNU Toolchain V2.6.0 20220715.

Compiling with MPI

To use the OpenMPI compiler wrappers (e.g. mpicc) on riscv-login, first load the openmpi/4.1.4_gcc12.2 and riscv64-linux/gnu-12.2 compiler module. Then the wrapper can be used along with the QEMU simulator included in riscv64-linux/gnu-12.2,

bash-4.2$ qemu-riscv64 /usr/local/share/riscv-software/openmpi4.1.4_gcc12.2/build/bin/mpicc [helloworld.c]

If you prefer to link the OpenMPI libraries manually, they can be found in

MPdir        = /usr/local/share/riscv-software/openmpi4.1.4_gcc12.2/build
MPinc        = -I$(MPdir)/include
MPlib        = $(MPdir)/lib/libmpi.a $(MPdir)/lib/libompitrace.a $(MPdir)/lib/libopen-rte.a  $(MPdir)/lib/libopen-pal.a -ldl