parallel  +  segmentation fault on arm  13508 Closed dasGringuen opened this Issue on Oct 9, 2015 · 4 comments Projects None yet Labels arm parallel Milestone No milestone Assignees No one assigned 4 participants  dasGringuen  tkelman  ViralBShah  yuyichao Notifications    dasGringuen dasGringuen commented on Oct 9, 2015  Hello  we are running Julia on the Red Pitaya platform using Debian Jessie armhf. Were are getting a segmentation fault while running the next code. You can find the code and the error log while running it with gdb.  Any hints?  Many thanks, Adrian Julia version:  root red-pitaya:  julia  . julia                 _    _       _ _ _ _     |  A fresh approach to technical computing    _      |  _   _     |  Documentation: http:  docs.julialang.org    _ _   _| |_  __ _   |  Type  ?help  for help.   | | | | | | |  _` |  |   | | |_| | | |  _| |  |  Version 0.4.0-rc4  2015-10-04 03:14 UTC   _  |\__'_|_|_|\__'_|  |   |__                    |  arm-linux-gnueabihf  julia    Code:  root red-pitaya:  julia  cat multicore_forloop-jl  A microbenchmark to demonstrate the effect of parallel for loops    $author: Manfred Mücke  $created: 20.9.2015  $lastchange: 29.9.2015    println        multicore_forloop-jl        println   Julia version: $VERSION     remove all workers which might be around rmprocs workers    println  Sequential run - available processes: $ nprocs         everywhere n 5000000   to scale test size    ------------------sequential s_s 0 for i   1:n  first run   s_s +  i 2 end s_s 0 t_seq    elapsed for i   1:n  measure   s_s +  i 2 end   add four worker processes on local machine addprocs 4  println  Parallel run - available workers:  ,nworkers       ------------------parallel  everywhere s_p 0 s_p    parallel  +  for i   1:n   first run   i 2 end  sync  everywhere sleep 1    global barrier  t_par    elapsed  parallel  +  for i   1:n   measure   i 2 end  if  myid      1    println   Results match: $ s_p    s_s   $s_p, $s_s      println    Sequential: \t$t_seq\n Parallel: \t$t_par\n Speed-Up: \t$ t_seq t_par \n     println                                                     end   remove all workers which might be around  rmprocs workers     Gdb log  root red-pitaya:  julia  gdb --args . julia . multicore_forloop-jl  GNU gdb  Debian 7.7.1+dfsg-5  7.7.1 Copyright  C  2014 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later  This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.  Type  show copying  and  show warranty  for details. This GDB was configured as  arm-linux-gnueabihf . Type  show configuration  for configuration details. For bug reporting instructions, please see: . Find the GDB manual and other documentation resources online at: . For help, type  help . Type  apropos word  to search for commands related to  word ... Reading symbols from . julia...done.  gdb  r Starting program:  root julia julia . multicore_forloop-jl  Thread debugging using libthread_db enabled  Using host libthread_db library   lib arm-linux-gnueabihf libthread_db.so.1 .  New Thread 0x12d20450  LWP 10644    WARNING: deprecated syntax  println    at  root julia multicore_forloop-jl:15. Use  println   instead.      multicore_forloop-jl       WARNING: deprecated syntax  println    at  root julia multicore_forloop-jl:17. Use  println   instead. Julia version: 0.4.0-rc4 WARNING: rmprocs: process 1 not removed Sequential run - available processes: 1   signal  11 : Segmentation fault  signal  11 : Segmentation fault  signal  11 : Segmentation fault  signal  11 : Segmentation fault  New Thread 0x10d4a450  LWP 10653    New Thread 0x1054a450  LWP 10654    New Thread 0xfd4a450  LWP 10655    New Thread 0xf54a450  LWP 10656   ERROR: LoadError: connect: connection refused  ECONNREFUSED   ...and 3 other exceptions.  while loading  root julia multicore_forloop-jl, in expression starting on line 55 UndefRefError    Thread 0xf54a450  LWP 10656  exited   Thread 0x1054a450  LWP 10654  exited   Thread 0xfd4a450  LWP 10655  exited   Thread 0x10d4a450  LWP 10653  exited   Thread 0x36ff1000  LWP 10641  exited   Inferior 1  process 10641  exited with code 01    tkelman tkelman added the arm label on Oct 9, 2015  dasGringuen dasGringuen commented on Oct 15, 2015  Hello,  I have tried also with a Raspberry pi and I'm getting the same segmentation fault errors. I followed the ARM compilation guide, enabled the debugging information and run it with GDB. Next you can find a more detailed output.  Could you please suggest how to proceed. We are looking forward on tracking this issue and fixing it.  Regards, Adrian Versioninfo    julia  versioninfo   Julia Version 0.4.0 Commit 0ff703b  2015-10-08 06:20 UTC  DEBUG build Platform Info:   System: Linux  arm-linux-gnueabihf    CPU: ARMv7 Processor rev 5  v7l    WORD_SIZE: 32   BLAS: libblas   LAPACK: liblapack   LIBM: libm   LLVM: libLLVM-3.6.1  Make.user  pi raspberrypi   julia $ cat Make.user  FORCE_ARMV7 1 LLVM_ASSERTIONS 1  override USE_SYSTEM_BLAS 1 override USE_SYSTEM_LAPACK 1 override USE_SYSTEM_LIBM 1 override USE_SYSTEM_FFTW 1 override USE_SYSTEM_GMP 1 override USE_SYSTEM_MPFR 1 override USE_SYSTEM_ARPACK 1   tkelman The Julia Language member tkelman commented on Oct 15, 2015  Best to use something separate like gist.github.com to post long logs, with just links here so this page isn't as bad to scroll through. Someone with access to an arm build will have to look into this.  ViralBShah The Julia Language member ViralBShah commented on Nov 25, 2015  I trimmed the output above. Also, this is easily reproduced just with:  viral julia-arm:  julia$ . julia -p 2 WARNING: unable to determine host cpu name. WARNING: unable to determine host cpu name. WARNING: unable to determine host cpu name.  signal  11 : Segmentation fault while loading no file, in expression starting on line 0  signal  11 : Segmentation fault while loading no file, in expression starting on line 0   ViralBShah ViralBShah added the parallel label on Nov 25, 2015  maleadt maleadt referenced this issue on Nov 30, 2015 Merged ARM ABI  14194  yuyichao The Julia Language member yuyichao commented on Jan 5  Close as a direct dup of  12344  and almost all of these issues on ARM  are just due to incompatible Clanguage ABI. Please feel free to report additional issues with  parallel on ARM after  14194 is merged.  yuyichao yuyichao closed this on Jan 5