# EPSPRIMMESetBlockSize

The maximum block size the code will try to use. The user should set this based on the architecture specifics of the target computer, as well as any a priori knowledge of multiplicities. The code does NOT require BlockSize > 1 to find multiple eigenvalues. For some methods, keeping BlockSize = 1 yields the best overall performance.

### Synopsis

    #include "slepceps.h"
    PetscErrorCode EPSPRIMMESetBlockSize(EPS eps,PetscInt bs)

Collective on EPS

### Input Parameters

| eps | - the eigenproblem solver context
| bs | - block size

### Options Database Key

-eps_primme_block_size - Sets the max allowed block size value

### Notes

If the block size is not set, the value established by primme_initialize is used.

### See Also

EPSPRIMMEGetBlockSize()

Location: src/eps/impls/external/primme/primme.c
Index of all EPS routines
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Index of all manual pages