Changes: Development

General

• Increase the minimum required CUDA Toolkit version to 11.4

• Change the policy so that documentation changes/fixes/additions are added to the main branch, not the release branch

• Change petscdiff to treat < in expected output as text that must match instead of suppressing differences from numerical output

• Change the make branch-review rule to [PETSC_LLM_CLI=command] [PETSC_LLM_MODEL=modelname] make branch-review. Add support for Gemini, Codex, OpenCode, and other LLM CLIs. Replace the use of CLAUDE_OPTS with PETSC_LLM_CLI_OPTS and PETSC_LLM_MODEL

Configure/Build

• Add providesDocs and docsDirs package attributes so that an external package’s sources can be cloned and scanned to generate PETSc manual pages when the documentation is built

• Add interface to LIBXSMM

Sys

• Add PetscGetConfiguration()

• Add PetscObjectViewSynchronizedFromOptions()

• Add PetscSetMPIThreadRequiredType()

• Add PetscOverrideIntelMKLCPUVendorDetection()

• Deprecate PETSC_MPI_THREAD_REQUIRED

• Add support for running PETSc applications as MCP servers that can be accessed by LLMs

• Add PetscRandomAppendOptionsPrefix() and PetscRandomGetOptionsPrefix()

• Add PetscCallLAPACKInfo() for calling LAPACK routines with an info argument where the caller requires an info value of 0 for the program to continue

Event Logging

PetscViewer

• Add support for writing CGNS descriptors on the base node: PetscViewerCGNSGetDescriptors(), PetscViewerCGNSRestoreDescriptors(), PetscViewerCGNSSetDescriptor()

• Add PetscViewerVTKWriteFn as the typedef prototype for the write() function passed to PetscViewerVTKAddField(). This addition requires no changes to user source code

PetscDraw

AO

IS

VecScatter / PetscSF

PF

Vec

• Add VecCreateSeqWithArrayAndMemType() and VecCreateMPIWithArrayAndMemType() to create array-style standard, CUDA, or HIP vectors from memory of a specified PetscMemType

• Add VecSetStdBasis() API to set a vector to the i-th standard basis vector

• Change the behavior of VecPointwiseDivide() implementing w = x / y: if a particular y[i] is zero and x[i] is also zero, w[i] is set to one (before it was set to zero).

PetscSection

PetscPartitioner

Mat

• Add MATPRODUCT_PtAP support for MATDIAGONAL and MATCONSTANTDIAGONAL

• Add MATPRODUCT_AB support for MATDIAGONAL and MATCONSTANTDIAGONAL with any matrix type

• Add MatSeqAIJGetKokkosView(), MatSeqAIJRestoreKokkosView(), MatSeqAIJGetKokkosViewWrite() and MatSeqAIJRestoreKokkosViewWrite() to the public API

• Change MatSeqAIJCUSPARSEGetIJ(), MatSeqAIJCUSPARSERestoreIJ(), MatSeqAIJHIPSPARSEGetIJ() and MatSeqAIJHIPSPARSERestoreIJ() to return PetscInt indices instead of int

• Add MatNormApproximate() to compute matrix norms approximately

• Add MatGetMultPetscSF() to access the PetscSF used to communicate off-process vector entries in MatMult() for MATMPIAIJ, MATMPIBAIJ, MATMPISBAIJ, MATMPIDENSE, and MATMPISELL

• Change MATSEQSBAIJ behavior in MatPermute() and MatDiagonalScale() to use MATSEQBAIJ when the result is not necessarily symmetric

• Change MatGetValues() to respect the row or column orientation set with MatSetOption(mat, MAT_ROW_ORIENTED, ...). This will break current code that calls MatSetOption(mat, MAT_ROW_ORIENTED, PETSC_FALSE) and uses MatGetValues()

• Add new MatType MATSEQBAIJLIBXSMM and MATMPIBAIJLIBXSMM

MatCoarsen

PC

• Add PCGAMGSetProlongatorFilter() and PCGAMGGetProlongatorFilter() to set/get the threshold for filtering small entries from the prolongator in PCGAMG

• Add PCAIR and PCPFLAREINV manual pages, generated from the PFLARE sources when the documentation is built

• Add PCParametersInitialize

• Fix PCMG to honor PCSetUseAmat(pc, PETSC_FALSE) at all levels

KSP

• Fix for KSP pre- and post-solve callbacks, that can now be used together with Eisenstat and Walker trick for SNES

• Add KSPPreSolve() and KSPPostSolve() to run the registered KSP pre/post solve callbacks

• Add KSPIDR — IDR(s) Induced Dimension Reduction Krylov solver (biorthogonal variant)

• Add KSPIDRSetS(), KSPIDRGetS(), KSPIDRSetRandom(), KSPIDRGetRandom(), KSPIDRSetCosine(), and KSPIDRGetCosine()

• Deprecate KSPMonitorResidualShort() and -ksp_monitor_short, remove the preconditioned_residual_short monitor registry name

SNES

• Change SNESSetUp() to not overwrite the NPC application context if one has previously been set on the NPC

• Change SNESComputeJacobian() to call the user-provided Jacobian function when a left NPC is active and the solver is not SNESASPIN

• Add support for nonlinear preconditioners with a DM different from the parent SNES DM. Calling SNESSetNPC() will no longer enforce default parameters on the npc.

• Change -snes_mf to respect an explicitly set PC type instead of silently overriding it with PCNONE; an explicitly requested PC that requires an assembled matrix now errors

• Deprecate SNESMonitorDefaultShort() and -snes_monitor_short

• Add SNESFASSetUseCoarseCorrectionLineSearch() and -snes_fas_use_coarse_correction_linesearch to implement the algorithm in [Nas00].

• Add SNESFASGetCoarseCorrectionLineSearch()

• Change default linesearch for SNESFAS with SNESFASType of SNES_FAS_ADDITIVE to SNESLINESEARCHSECANT

SNESLineSearch

• Deprecate SNESLINESEARCHBASIC in favor of SNESLINESEARCHNONE

TS

• Add DMTSSetIFunctionPre()

• Add TSDiscGradSetImplicitFormulation()

• Expose TSDiscGradGetX0AndXdot() and TSDiscGradRestoreX0AndXdot()

• Add TSIsImplicit() that indicates if the TSType is implicit and uses SNES or KSP

TAO

• Add TaoGetDM() and TaoSetDM()

• Deprecate TaoMonitorDefaultShort(), -tao_monitor_short, and -tao_monitor_short_interval

• Change the deprecated TaoSMonitor() and -tao_smonitor to use the full-precision default monitor

• Add TaoGetConvergedReasonString() to retrieve a human readable string describing the TaoConvergedReason

TaoTerm

PetscRegressor

PetscDA

• Add the PetscDALETKFLocalizationType enum (PETSCDA_LETKF_LOC_NONE, PETSCDA_LETKF_LOC_GASPARI_COHN, PETSCDA_LETKF_LOC_GAUSSIAN, PETSCDA_LETKF_LOC_BOXCAR) selecting the LETKF localization kernel

• Add PetscDALETKFSetLocalizationType(), PetscDALETKFGetLocalizationType(), PetscDALETKFSetLocalizationRadius(), PetscDALETKFGetLocalizationRadius(), and PetscDALETKFSetLocalizationCoordinates(); the localization matrix is built lazily from these distance-based kernel parameters

• Add PetscDALETKFResetLocalization() to drop the cached localization matrix so the next analysis rebuilds it from the current kernel parameters

• Remove PETSCDAETKF; use PETSCDALETKF with PetscDALETKFSetLocalizationType(da, PETSCDA_LETKF_LOC_NONE) for identical behavior

• Remove PetscDAEnsembleSetSqrtType(), PetscDAEnsembleGetSqrtType(), the PetscDASqrtType enum (PETSCDA_SQRT_CHOLESKY, PETSCDA_SQRT_EIGEN), and the -petscda_ensemble_sqrt_type option; the symmetric-eigendecomposition square root is now the only path

• Remove PetscDALETKFSetLocalization(); use the distance-based API PetscDALETKFSetLocalizationType(), PetscDALETKFSetLocalizationRadius(), and PetscDALETKFSetLocalizationCoordinates() instead

• Remove PetscDALETKFSetObsPerVertex() and PetscDALETKFGetObsPerVertex(); per-vertex observation counts are now derived from the distance-based localization kernel

• Remove PetscDALETKFGetLocalizationMatrix(); the localization matrix is an internal cached object built lazily on the first analysis. Callers that previously supplied this matrix should switch to PetscDALETKFSetLocalizationCoordinates() and let the implementation build the matrix from the chosen kernel

• Change the LETKF distance-based periodicity convention: per-axis periodicity is now activated by bd[d] > 0.0 (the period), and negative bd[d] now raises PETSC_ERR_ARG_OUTOFRANGE; previously any non-zero bd[d] (including negative values) enabled periodicity

• Add PetscDAEnsembleForecastFn typedef for the PetscDAEnsembleForecast() model callback

• Change the PetscDAEnsembleForecast() model callback signature from (Vec, Vec, PetscCtx) to (Mat, PetscCtx); the model now receives the entire ensemble matrix and advances all members in place. Existing per-member callbacks should iterate over the columns with MatDenseGetColumnVec()/MatDenseRestoreColumnVec() (see ShallowWaterStep2D() in src/ml/da/tutorials/ex4.c)

• Change -petscda_view to fire at the tail of every PetscDAEnsembleAnalysis() call (mirroring KSPSolve()/SNESSolve()), so it now emits once per analysis cycle rather than once per run; code that wants a single end-of-run snapshot should call PetscDAView() explicitly after the assimilation loop

DM

• Change DMLabelPropagatePush() to take a reduce operator

• Add DMKSPSetCreateOperators() to let the DM provide a pair of application specific Mat objects to inner KSP solvers.

DMSwarm

• Add DMSwarmProjectFields() and DMSwarmProjectGradientFields()

• Add DMSwarmSort class

• Add DMSwarmSortDestroy() and DMSwarmSortView()

• Allow DMSwarmCellDMSetSort() to take in NULL and clear the sort

• Add DMSwarmPreallocateMassMatrix() and DMSwarmFillMassMatrix()

DMPlex

• Add DMPlexSetClosurePermutationLexicographic()

• Add DMPlexDrawCell()

• Add DMPlexLabelCompleteStar()

• Add DMPlexVecGetClosureAtDepth()

• Add an extra communicator argument to DMPlexFilter() to allow extracting local meshes

• Add DMPlexCopyFlags()

• Add DMPlexRebalanceSharedLabelPoints()

• Add DMPlexCheckLabel() and DMPlexReconcileLabel()

• Change CGNS viewer to use multi-component read/write interface for better performance

• Add DMPlexTransformOrderSupports()

• Add DMPlexLabelCohesiveCheck()

• Add DMPlexCheckOrientationLabel()

• Change DMPlexLabelCohesiveComplete() to remove split argument

• Add DM_COORD_MAP_TORUS

• Add DM_COORD_MAP_ROTATE

• Add DM_SHAPE_DIIID

• Add DMPlexTriangleSetAngleBound(), DMPlexTriangleGetAngleBound(), DMPlexTetgenSetRadiusEdgeBound(), DMPlexTetgenGetRadiusEdgeBound(), DMPlexTetgenSetDihedralBound(), DMPlexTetgenGetDihedralBound()

FE/FV

DMNetwork

DMStag

DT

• Add PetscWeakFormGetKeys()

Fortran