Dear ADF users,

The mysterious error messages related to CIO (input/output using C routines)
are often related to a full hard disk. It will occur when a large calculation
is run on a system with relatively little disk space. It will occur more
rapidly if the basis and fit functions are written to disk
(option DISK BASIS FIT). The (default) direct SCF option is to be preferred
(DISK NOBAS NOFIT). In the current version the default for RESPONSE
calculations (if the keywords RESPONSE or EXCITATIONS occur in the input)
is still DISK BAS NOFIT, so it uses (too) much disk space.

Calculations of this type will run more efficiently if one specifies in the
INPUT file:

DISK NOBAS NOFIT.

Certainly less disk space will be used. The results should be identical.

So, if you encounter a CIO_ERROR:

1) Have a look at the file space in the temporary directory where the
   ADF files like TAPE10 etc. are located.

2) There are several possible work-arounds:
   a) if basis and/or fit sets are written to file in your calculation
      (for example in a RESPONSE or EXCITATION calculation), you can
      solve the problem with DISK NOBAS NOFIT
   b) if you have a parallel version: use more processors. The disk usage
      per processor will decrease significantly.
   c) Use a machine with a larger hard disk.

If you have checked that this is not the cause of your CIO_ERROR, please
send a bug report to bugs_at_scm.com.

Best regards,
Stan van Gisbergen, SCM
Received on 2000-09-28 17:24:35