The number of characters needed to print a double in scientific format
is 8 plus the number of decimal places; e.g., -6.453452e-231 (6 decimal
places, 14 characters). This has been set in writeFile.C, replacing a
value of 7. Presumably, the case of three digits in the exponent was not
considered when this was first implemented. This change ensures at least
one character of whitespace between tabulated numbers.
This resolves bug report https://bugs.openfoam.org/view.php?id=2801
When specifying the averaging data, a new `windowType` option is
available, taking the values:
- none: no windowing
- approximate: past functionality (v1706 and earlier)
- exact: exact moving average - will store and write (for restart) all
fields in the window
Original commit message:
------------------------
Parallel IO: New collated file format
When an OpenFOAM simulation runs in parallel, the data for decomposed fields and
mesh(es) has historically been stored in multiple files within separate
directories for each processor. Processor directories are named 'processorN',
where N is the processor number.
This commit introduces an alternative "collated" file format where the data for
each decomposed field (and mesh) is collated into a single file, which is
written and read on the master processor. The files are stored in a single
directory named 'processors'.
The new format produces significantly fewer files - one per field, instead of N
per field. For large parallel cases, this avoids the restriction on the number
of open files imposed by the operating system limits.
The file writing can be threaded allowing the simulation to continue running
while the data is being written to file. NFS (Network File System) is not
needed when using the the collated format and additionally, there is an option
to run without NFS with the original uncollated approach, known as
"masterUncollated".
The controls for the file handling are in the OptimisationSwitches of
etc/controlDict:
OptimisationSwitches
{
...
//- Parallel IO file handler
// uncollated (default), collated or masterUncollated
fileHandler uncollated;
//- collated: thread buffer size for queued file writes.
// If set to 0 or not sufficient for the file size threading is not used.
// Default: 2e9
maxThreadFileBufferSize 2e9;
//- masterUncollated: non-blocking buffer size.
// If the file exceeds this buffer size scheduled transfer is used.
// Default: 2e9
maxMasterFileBufferSize 2e9;
}
When using the collated file handling, memory is allocated for the data in the
thread. maxThreadFileBufferSize sets the maximum size of memory in bytes that
is allocated. If the data exceeds this size, the write does not use threading.
When using the masterUncollated file handling, non-blocking MPI communication
requires a sufficiently large memory buffer on the master node.
maxMasterFileBufferSize sets the maximum size in bytes of the buffer. If the
data exceeds this size, the system uses scheduled communication.
The installation defaults for the fileHandler choice, maxThreadFileBufferSize
and maxMasterFileBufferSize (set in etc/controlDict) can be over-ridden within
the case controlDict file, like other parameters. Additionally the fileHandler
can be set by:
- the "-fileHandler" command line argument;
- a FOAM_FILEHANDLER environment variable.
A foamFormatConvert utility allows users to convert files between the collated
and uncollated formats, e.g.
mpirun -np 2 foamFormatConvert -parallel -fileHandler uncollated
An example case demonstrating the file handling methods is provided in:
$FOAM_TUTORIALS/IO/fileHandling
The work was undertaken by Mattijs Janssens, in collaboration with Henry Weller.
There are a few issues:
- error would only throw exceptions if not parallel
- if we change this we also need to make sure the functionObjectList
construction is synchronised
- bounding box overlap was not returning the correct status so the code
to avoid the issue of 'badly formed bounding box' was not triggered.
- consolidate word::validated() into word::validate() and also allow
as short form for string::validate<word>(). Also less confusing than
having similarly named methods that essentially do the same thing.
- more consistent const access when iterating over strings
- add valid(char) for keyType and wordRe
- error::throwExceptions(bool) returning the previous state makes it
easier to set and restore states.
- throwing() method to query the current handling (if required).
- the normal error::throwExceptions() and error::dontThrowExceptions()
also return the previous state, to make it easier to restore later.
- added an explicit print, but only report profiling to the log
file from master process.
We don't wish to overwrite any profiling that was conducted during
the simulation. Besides which, we don't have a proper Time object
for handling the write nicely either.
- ensure proper and sensible handling of empty names.
Eg, isDir(""), isFile("") are no-ops, and avoid file-stat
- rmDir:
* optional 'silent' option to suppress messages.
* removes all possible sub-entries, instead of just giving up on
the first problem encountered.
- reduced code duplication in etcFiles
ENH: provide WM_USER_RESOURCE_DIRNAME define (in foamVersion.H)
- this is still a hard-coded value, but at least centrally available
- this makes it possible to perform additional operations
on surface values that have been previously sampled.
- support vectorField for weighting operations.
- reduce overhead by avoiding creation of weight fields, Sf fields
and combined surface geometries unless they are actually required.
- extend some similar concepts and operations to volFieldValue
