<div dir="ltr"><div style="word-wrap:break-word">After running in debug mode it seems that the GAMG solver indeed did not converge, however throwing the error leads to SIGABRT (backtrace and frames are below).<br></div><div style="word-wrap:break-word">It is still very suspicious why would solving for (unchanged) mass matrix wouldn't converge inside SLEPc's spectral transformation.<br></div><div style="word-wrap:break-word"><br></div><div style="word-wrap:break-word">p.s. valgrind takes enormous amount of time on this problem, <br></div><div style="word-wrap:break-word">will try to leave it over the weekend.<br></div><div style="word-wrap:break-word"><br></div><div style="word-wrap:break-word">Denis.<br></div><div style="word-wrap:break-word"><br></div><div style="word-wrap:break-word">===============<br>Program received signal SIGABRT, Aborted.<br>0x00007fffea87fcc9 in __GI_raise (sig=sig@entry=6)<br>    at ../nptl/sysdeps/unix/sysv/linux/raise.c:56<br>56      ../nptl/sysdeps/unix/sysv/linux/raise.c: No such file or directory.<br>(gdb) bt<br>#0  0x00007fffea87fcc9 in __GI_raise (sig=sig@entry=6)<br>    at ../nptl/sysdeps/unix/sysv/linux/raise.c:56<br>#1  0x00007fffea8830d8 in __GI_abort () at abort.c:89<br>#2  0x00007fffeb790c91 in PetscTraceBackErrorHandler (comm=0x2a09bd0, <br>    line=798, fun=0x7fffed0e24b9 <__func__.20043> "KSPSolve", <br>    file=0x7fffed0e1620 "/home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/ksp/ksp/interface/itfunc.c", n=91, p=PETSC_ERROR_INITIAL, <br>    mess=0x7fffffffac30 "KSPSolve has not converged", ctx=0x0)<br>    at /home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/sys/error/errtrace.c:243<br>#3  0x00007fffeb78b8b9 in PetscError (comm=0x2a09bd0, line=798, <br>    func=0x7fffed0e24b9 <__func__.20043> "KSPSolve", <br>    file=0x7fffed0e1620 "/home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/ksp/ksp/interface/itfunc.c", n=91, p=PETSC_ERROR_INITIAL, <br>    mess=0x7fffed0e1e7a "KSPSolve has not converged")<br>    at /home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/sys/error/err.c:377<br>#4  0x00007fffec75e1e7 in KSPSolve (ksp=0x367227d0, b=0x35b285c0, x=0x35d89250)<br>    at /home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/ksp/ksp/interface/itfunc.c:798<br>#5  0x00007fffe32a8657 in STMatSolve (st=0x3672d820, b=0x35b285c0, <br>    x=0x35d89250)<br>    at /home/davydden/.hashdist/tmp/slepc-22nb32nbgvhx/src/sys/classes/st/interface/stsles.c:166<br>---Type <return> to continue, or q <return> to quit---q<br>Quit<br>(gdb) f 5<br>#5  0x00007fffe32a8657 in STMatSolve (st=0x3672d820, b=0x35b285c0, <br>    x=0x35d89250)<br>    at /home/davydden/.hashdist/tmp/slepc-22nb32nbgvhx/src/sys/classes/st/interface/stsles.c:166<br>166       ierr = KSPSolve(st->ksp,b,x);CHKERRQ(ierr);<br>(gdb) f 4<br>#4  0x00007fffec75e1e7 in KSPSolve (ksp=0x367227d0, b=0x35b285c0, x=0x35d89250)<br>    at /home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/ksp/ksp/interface/itfunc.c:798<br>798      
 if (ksp->errorifnotconverged && ksp->reason < 0) 
SETERRQ(comm,PETSC_ERR_NOT_CONVERGED,"KSPSolve has not converged");<br>(gdb) f 3<br>#3  0x00007fffeb78b8b9 in PetscError (comm=0x2a09bd0, line=798, <br>    func=0x7fffed0e24b9 <__func__.20043> "KSPSolve", <br>    file=0x7fffed0e1620 "/home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/ksp/ksp/interface/itfunc.c", n=91, p=PETSC_ERROR_INITIAL, <br>    mess=0x7fffed0e1e7a "KSPSolve has not converged")<br>    at /home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/sys/error/err.c:377<br>377       if (!eh) ierr = PetscTraceBackErrorHandler(comm,line,func,file,n,p,lbuf,0);<br>(gdb) f 2<br>#2  0x00007fffeb790c91 in PetscTraceBackErrorHandler (comm=0x2a09bd0, <br>    line=798, fun=0x7fffed0e24b9 <__func__.20043> "KSPSolve", <br>    file=0x7fffed0e1620 "/home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/ksp/ksp/interface/itfunc.c", n=91, p=PETSC_ERROR_INITIAL, <br>    mess=0x7fffffffac30 "KSPSolve has not converged", ctx=0x0)<br>    at /home/davydden/.hashdist/tmp/petsc-hujktg3j6hq7/src/sys/error/errtrace.c:243<br>243         abort();<br>(gdb) f 1<br>#1  0x00007fffea8830d8 in __GI_abort () at abort.c:89<br>89      abort.c: No such file or directory.<br><br></div></div>