On Tue, Jan 21, 2025 at 9:46 AM Daniel Stone <daniel.st...@opengosim.com> wrote:
> Is there a quick way for me to find out which version of > PETSc KSPConvergedDefaultCreate() was introduced with? > I'll likely need to conditionally pragma-out these calls for back > compatibility. > We have changes docs: https://urldefense.us/v3/__https://petsc.org/main/changes/__;!!G_uCfscf7eWS!cAwR4aLIcKH3Pn0R90bQMD51mNRpiPcM7Ic_X9IQC6ANOcmJIekcW1TYwAdodLUkR1pyNfHatMuaoZiRhrFA$ main *$:~/PETSc4/petsc/petsc-pylith$ find doc/changes/ | xargs grep KSPConvergedDefaultCreate doc/changes//35.rst: ``KSPConvergedDefaultCreate()``, Thanks, Matt Thanks, > > Daniel > > On Tue, Jan 21, 2025 at 1:16 PM Barry Smith <bsm...@petsc.dev> wrote: > >> >> Yes, that can be passed in also with KSPSetConvergenceTest() >> >> >> On Jan 21, 2025, at 4:25 AM, Daniel Stone <daniel.st...@opengosim.com> >> wrote: >> >> That works wonderfully, thanks! Should be paired with >> >> call KSPConvergedDefaultDestroy(ctx,ierr) >> >> I think. >> >> Best Regards, >> >> Daniel >> >> >> >> On Mon, Jan 20, 2025 at 3:20 PM Barry Smith <bsm...@petsc.dev> wrote: >> >>> >>> David, >>> >>> KSPConvergedDefault() now takes a non-NULL context that must be >>> provided. I have attached a modified version of ex5f.F90 that demonstrates >>> how it is constructured before being passed to KSPSetConvergenceTest(). >>> >>> Barry >>> >>> >>> > On Jan 20, 2025, at 8:54 AM, Daniel Stone <daniel.st...@opengosim.com> >>> wrote: >>> > >>> > Hello PETSc Community, >>> > >>> > I think I've found a bug - >>> > >>> > Go to $PETSC_DIR/src/ksp/ksp/tutorials/ >>> > >>> > open ex5f.F90, and add the following line in MyKSPConverged(), say >>> around line 336: >>> > >>> > call KSPConvergedDefault(ksp,n,rnorm,flag,dummy,ierr) >>> > >>> > It should make sense why someone would want to do this - within a >>> definition of custom convergence behaviour, get the default convergence >>> flags, and, based on certain conditions, overwrite it. >>> > >>> > Now, building and running the exercise, making sure to include the >>> flag to use the custom convergence: >>> > >>> > >>> > boston@boston-SYS-540A-TR:~/DATA_DRIVE/PETSC_DIRS/petsc_3.22/src/ksp/ksp/tutorials$ >>> ./ex2f -my_ksp_convergence >>> > [0]PETSC ERROR: >>> ------------------------------------------------------------------------ >>> > [0]PETSC ERROR: Caught signal number 11 SEGV: Segmentation Violation, >>> probably memory access out of range[...] >>> > >>> > From my debugging, the issue is at line 1520 of iterativ.c: >>> > >>> > KSPConvergedDefaultCtx *cctx = (KSPConvergedDefaultCtx *)ctx; >>> > >>> > Because a dummy is used for the context object, this cast fails (my >>> debugger says "cannot access memory..." for cctx). Then the crash happens >>> when trying to access members of cctx: >>> > >>> > if (cctx->convmaxits && n >= ksp->max_it) { >>> > >>> > >>> > I'm not sure how to fix it. Crucially, we must note that that this did >>> work in older versions of PETSc - I can repeat this test in 3.19.1, for >>> example, and it works fine - a debugger shows the cast succeeding and >>> producing some >>> > defaulted version of the ctx object, the subsequent crash does not >>> happen, etc. >>> > >>> > Does anybody have any advice for working around this for the time >>> being? A piece of software I work with uses a custom ksp convergence test >>> in the manner described above, and is only functional with older versions >>> of petsc because of this. >>> > Like in ex2f, I have no need of the ctx object, and just as in ex2f, I >>> use 0 instead. >>> > >>> > Things I'll try next: defining a proper ctx object (I use 0, like in >>> ex2f), or looking for some PETSC_NULL_CTX definition somewhere. >>> > >>> > Many Thanks, >>> > >>> > Daniel >>> > >>> > >>> > >>> >>> >> -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://urldefense.us/v3/__https://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!cAwR4aLIcKH3Pn0R90bQMD51mNRpiPcM7Ic_X9IQC6ANOcmJIekcW1TYwAdodLUkR1pyNfHatMuaoR6gbnMD$ <https://urldefense.us/v3/__http://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!cAwR4aLIcKH3Pn0R90bQMD51mNRpiPcM7Ic_X9IQC6ANOcmJIekcW1TYwAdodLUkR1pyNfHatMuaobbVeGa1$ >
