Re: [petsc-users] -snes_fd for problems with residuals with non-continuous first derivative?

>39 SNES Function norm 3.758101652998e-08 > 0 KSP preconditioned resid norm 1.931834799209e-02 true resid norm > 3.758101652998e-08 ||r(i)||/||b|| 1.e+00 > 1 KSP preconditioned resid norm 5.958979968059e-16 true resid norm > 2.588244438237e-18 ||r(i)||/||b||

Re: [petsc-users] -snes_fd for problems with residuals with non-continuous first derivative?

Let me suggest that you grab a hold of Simo and Hughes, Computational Inelasticity, Springer-Verlag (1998). It explains a lot about how to set up this problem -- in particular Chapter 1 gives a comprehensive one-dimensional tutorial on everything you need to know. On 7/5/17 9:39 AM,

Re: [petsc-users] -snes_fd for problems with residuals with non-continuous first derivative?

On Wed, Jul 5, 2017 at 9:39 AM, Maximilian Hartig wrote: > I do not clearly understand the discrimination between local and global > plasticity. I do have areas where I expect the behaviour to be elastic and > other areas where I expect elasto-plastic behaviour. >

Re: [petsc-users] -snes_fd for problems with residuals with non-continuous first derivative?

I do not clearly understand the discrimination between local and global plasticity. I do have areas where I expect the behaviour to be elastic and other areas where I expect elasto-plastic behaviour. Inertia effects are of importance and hence I need second order temporal derivatives of my

Re: [petsc-users] -snes_fd for problems with residuals with non-continuous first derivative?

Plasticity should not cause any major difficulties with your global iterations. Your residuals look your load steps are elastic all the way until it fails. Are you sure that your applied boundary conditions have a unique solutions? In particular, are you applying forces to a perfect

Re: [petsc-users] -snes_fd for problems with residuals with non-continuous first derivative?

The solver goes on for some timesteps, then it gets hung up in step 10. The output is as follows: 28 SNES Function norm 7.825649542035e-06 0 KSP preconditioned resid norm 5.335581451751e+00 true resid norm 7.825649542035e-06 ||r(i)||/||b|| 1.e+00 1 KSP preconditioned

Re: [petsc-users] Is OpenMP still available for PETSc?

For a given use case, you may want to try all possible t and c such that t*c=n : stick to the best one. Now, if you modify resources (t/c) and you get different timing/iterations, this seems logical to me: blocks, overlap, ... (and finally convergence) will differ so comparison does no more

Re: [petsc-users] Is OpenMP still available for PETSc?

Thank you:) Few notes on what you wrote 1. I always try to keep t*c=number of cores, however for 64 core KNL which has hyperthreading switched on (cpuinfo shows 256 cores) t*c should be 64 or 256 (in other words: is t=64 and c=4 correct?) ? 2. I noticed that for the same input data I

Re: [petsc-users] Is OpenMP still available for PETSc?

Thank you:) Few notes on what you wrote 1. I always try to keep t*c=number of cores, however for 64 core KNL which has hyperthreading switched on (cpuinfo shows 256 cores) t*c should be 64 or 256 (in other words: is t=64 and c=4 correct?) ? 2. I noticed that for the same input data I

Re: [petsc-users] Is OpenMP still available for PETSc?

The man page of slurm/sbatch is cumbersome. But, you may think of : 1. tasks "as MPI processus" 2. cpus "as threads" You should always set resources the most precise way when possible, that is (never use --tasks but prefer) to: 1. use --nodes=n. 2. use --tasks-per-node=t. 3. use