Sorry, try both with -ts_adapt_monitor
> On Dec 9, 2024, at 5:29 PM, Blondel, Sophie <sblon...@utk.edu> wrote: > > Hi Barry, > > I hope you are doing well. > > Attached are the output. To give a little more context, this is a "new" way > of running the code where multiple instances are created and communicate > together every few time steps (like coupling the code with itself in memory). > Here there are 3 instances that each have a separate TS object, plus one > "main" instance that doesn't solve anything but compute rates to exchange > between the other instances. > > Cheers, > > Sophie > From: Barry Smith <bsm...@petsc.dev> > Sent: Monday, December 9, 2024 15:12 > To: Blondel, Sophie <sblon...@utk.edu> > Cc: petsc-users@mcs.anl.gov <petsc-users@mcs.anl.gov>; > xolotl-psi-developm...@lists.sourceforge.net > <xolotl-psi-developm...@lists.sourceforge.net> > Subject: Re: [petsc-users] "-ts_exact_final_time matchstep" leads to > DIVERGED_STEP_REJECTED > > > >> On Dec 9, 2024, at 2:56 PM, Blondel, Sophie via petsc-users >> <petsc-users@mcs.anl.gov> wrote: >> >> Hi, >> >> I am trying to understand a strange behavior I'm encountering: when running >> my application with "-ts_exact_final_time stepover" everything goes well, >> but when I switch to "matchstep" I get DIVERGED_STEP_REJECTED before the >> first time step is finished. > > This is in the very first time-step in TSSolve? > > Please run with -ts_monitor and send all the output (best for a short > time interval and do it twice once with -ts_exact_final_time stepover and > once with exact. > > Barry > > >> I tried increasing the maximum number of rejections and it just takes longer >> to diverge, and if I set the value to "unlimited" it is basically an >> infinite loop. >> >> Is there a way to check why is the step rejected? Could the "matchstep" >> option change tolerances somewhere that would cause that behavior? >> >> Let me know if I should provide more information. >> >> Best, >> >> Sophie Blondel > > <stepover.txt><matchstep.txt>
