# Failed to run program parallely

**URL:** <https://discourse.julialang.org/t/failed-to-run-program-parallely/34560>\
**Category:** New to Julia\
**Tags:** question\
**Created:** [February 13, 2020, 6:13am UTC](https://discourse.julialang.org/t/failed-to-run-program-parallely/34560 "2020-02-13T06:13:05Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![tool](https://avatars.discourse-cdn.com/v4/letter/t/df705f/32.png) [@tool](https://discourse.julialang.org/u/tool)\
**Post date:** [February 13, 2020, 6:13am UTC](https://discourse.julialang.org/t/failed-to-run-program-parallely/34560/1 "2020-02-13T06:13:05Z")

</div>

I’m trying to run command “GB.f4” in GB.jl([GitHub - ederc/GroebnerBasis.jl: Julia wrapper for gb](https://github.com/ederc/GB.jl)).  
The command run without problems when it runs sigle thread.

julia\> using GB  
Welcome to Nemo version 0.16.2  
Nemo comes with absolutely no warranty whatsoever

julia\> R,I = GB.katsura\_8(65521);

julia\> H = GB.f4(I,nthrds=1);

But. when several threads, it doesn’t run, and cause segmentation fault.

julia\> using GB  
Welcome to Nemo version 0.16.2  
Nemo comes with absolutely no warranty whatsoever

julia\> R,I = GB.katsura\_8(65521);

julia\> H = GB.f4(I,nthrds=2);  
signal (11): Segmentation fault  
in expression starting at REPL[2]:1  
convert\_hashes\_to\_columns.\_omp\_fn.22 at /home/ubuntu/.julia/packages/GB/BMo7R/deps/usr/lib/libgb.so (unknown line)  
convert\_hashes\_to\_columns at /home/ubuntu/.julia/packages/GB/BMo7R/deps/usr/lib/libgb.so (unknown line)  
f4\_julia at /home/ubuntu/.julia/packages/GB/BMo7R/deps/usr/lib/libgb.so (unknown line)  
#f4#269 at /home/ubuntu/.julia/packages/GB/BMo7R/src/GB.jl:296  
#f4 at ./none:0  
unknown function (ip: 0x7fde7846e986)  
jl\_apply\_generic at /buildworker/worker/package\_linux64/build/src/gf.c:2197  
do\_call at /buildworker/worker/package\_linux64/build/src/interpreter.c:323  
eval\_value at /buildworker/worker/package\_linux64/build/src/interpreter.c:411  
eval\_stmt\_value at /buildworker/worker/package\_linux64/build/src/interpreter.c:362 [inlined]  
eval\_body at /buildworker/worker/package\_linux64/build/src/interpreter.c:772  
jl\_interpret\_toplevel\_thunk\_callback at /buildworker/worker/package\_linux64/build/src/interpreter.c:884  
unknown function (ip: 0xfffffffffffffffe)  
unknown function (ip: 0x7fde9414988f)  
unknown function (ip: 0x6)  
jl\_interpret\_toplevel\_thunk at /buildworker/worker/package\_linux64/build/src/interpreter.c:893  
jl\_toplevel\_eval\_flex at /buildworker/worker/package\_linux64/build/src/toplevel.c:815  
jl\_toplevel\_eval\_flex at /buildworker/worker/package\_linux64/build/src/toplevel.c:764  
jl\_toplevel\_eval\_flex at /buildworker/worker/package\_linux64/build/src/toplevel.c:764  
jl\_toplevel\_eval\_in at /buildworker/worker/package\_linux64/build/src/toplevel.c:844  
eval at ./boot.jl:330  
jl\_apply\_generic at /buildworker/worker/package\_linux64/build/src/gf.c:2191  
eval\_user\_input at /buildworker/worker/package\_linux64/build/usr/share/julia/stdlib/v1.2/REPL/src/REPL.jl:86  
macro expansion at /buildworker/worker/package\_linux64/build/usr/share/julia/stdlib/v1.2/REPL/src/REPL.jl:118 [inlined]  
#26 at ./task.jl:268  
jl\_apply\_generic at /buildworker/worker/package\_linux64/build/src/gf.c:2191  
jl\_apply at /buildworker/worker/package\_linux64/build/src/julia.h:1614 [inlined]  
start\_task at /buildworker/worker/package\_linux64/build/src/task.c:596  
unknown function (ip: 0xffffffffffffffff)  
Allocations: 14110728 (Pool: 14108613; Big: 2115); GC: 28  
Segmentation fault (コアダンプ)

I’m new to Julia and I don’t know what to do.  
I’m using Julia 1.2.0., OS is Ubuntu 18.04