:orphan:
# KSPSetMatSolveBatchSize
Sets the maximum number of columns treated simultaneously in `KSPMatSolve()`.
## Synopsis
```
#include "petscksp.h"
#include "petscmat.h"
PetscErrorCode KSPSetMatSolveBatchSize(KSP ksp, PetscInt bs)
```
Logically Collective
## Input Parameters
- ***ksp -*** iterative context
- ***bs -*** batch size
## See Also
[](ch_ksp), `KSPMatSolve()`, `KSPGetMatSolveBatchSize()`, `-mat_mumps_icntl_27`, `-matmatmult_Bbn`
## Level
advanced
## Location
src/ksp/ksp/interface/itfunc.c
## Examples
src/ksp/ksp/tutorials/ex76.c
src/ksp/ksp/tutorials/ex77.c
src/ksp/ksp/tutorials/ex77f.F90
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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/ksp/ksp/interface/itfunc.c)
[Index of all KSP routines](index.md)
[Table of Contents for all manual pages](/manualpages/index.md)
[Index of all manual pages](/manualpages/singleindex.md)