Remove uses of /dev/null in Graph500 benchmark

[OlivierNicole]

This an attempt to temporary fix #406, although increasing available disk size would be better. The Graph500 benchmarks should now produce file that are around 250 MB, rather than 1 GB.

[shakthimaan]

Can you also remove /dev/null from the run_config.json file? Why is this needed? It is not handled by rungen.

    { "params": "-scale 21 -edgefactor 16 -ndomains 1 /dev/null", "paramwrapper": "taskset --cpu-list 2-13" },
    { "params": "-scale 21 -edgefactor 16 -ndomains 2 /dev/null", "paramwrapper": "taskset --cpu-list 2-13" },
    { "params": "-scale 21 -edgefactor 16 -ndomains 4 /dev/null", "paramwrapper": "taskset --cpu-list 2-13" },
    { "params": "-scale 21 -edgefactor 16 -ndomains 8 /dev/null", "paramwrapper": "taskset --cpu-list 2-13" },
    { "params": "-scale 21 -edgefactor 16 -ndomains 12 /dev/null", "paramwrapper": "taskset --cpu-list 2-13" },
    { "params": "-scale 21 -edgefactor 16 -ndomains 16 /dev/null", "paramwrapper": "taskset --cpu-list 2-13,16-27" },
    { "params": "-scale 21 -edgefactor 16 -ndomains 20 /dev/null", "paramwrapper": "taskset --cpu-list 2-13,16-27" },
    { "params": "-scale 21 -edgefactor 16 -ndomains 24 /dev/null", "paramwrapper": "taskset --cpu-list 2-13,16-27" }

Reference:

1. https://github.com/ocaml-bench/sandmark/blob/main/multicore_parallel_navajo_run_config.json
2. https://github.com/ocaml-bench/sandmark/blob/main/multicore_parallel_run_config.json

[OlivierNicole]

Sorry for the delay. I removed uses of /dev/null and replaced with the relative filename edges.data.

[OlivierNicole]

Given that the disk usage issue seems resolved, I propose to go back to the original parameters for the Graph500 benchmarks, and keep only the removal of /dev/null in this PR.

[shakthimaan]

Can you please rebase the PR to the latest changes in the main branch?

[OlivierNicole]

Done.

[shakthimaan]

LGTM!