- includes restructuring and simplification of low-level ensight part
handling and refactor of backends to improve code reuse.
foamToEnsight
-------------
* new cellZone support.
This was previously only possible via a separate foamToEnsightParts
utility that was not parallelized.
* support for point fields.
* `-nearCellValue` option (as per foamToVTK)
* data indexing now uses values from the time index.
This is consistent with the ensightWrite function object and
can help with restarts.
* existing ensight directories are removed, unless the -no-overwrite
option is supplied
foamToEnsightParts
------------------
* now redundant and removed.
ensightOutputSurface (new class)
--------------------------------
* a lightweight wrapper for point/face references that is tailored
for the ensightSurfaceWriter. It uses compact face/point information
and is serial only, since this is the format requirements from the
surfaceWriter class.
ensightMesh (revised class)
---------------------------
* now only holds a polyMesh reference, which removes its dependency
on finiteVolume and allows it to be relocated under fileFormats
instead of conversion.
Removed classes: ensightParts, ensighPartFaces, ensightPartCells
- these were used by foamToEnsightParts, but not needed anymore.
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.
- in specific cases it can be useful to suppress searching the instances.
For example, if one only wishes to check if a "points" is available at
the given time instance, without searching backwards through all
times.
- eliminate ensightAsciiStream, ensightBinaryStream, ensightStream in
favour of using ensightFile and ensightGeoFile classes throughout.
- encapsulate mesh-parts sorting with the ensightCells, ensightFaces
class.
- handle of patches/faceZones entirely within ensightMesh for a lighter
interaction with field output. Both faceZones and point fields need
more testing to see if they behave properly for all cases.
- move some output functionality into its own namespace
'ensightOutput', move into a library.
- use the ensightCase class to open new ensight output streams
in the proper sub-directory locations.
- Less looping when detecting lagrangian clouds and their fields.
- Avoid using Time::setTime() and IOobjectList in tight loops.
They both kill performance immensely.
ENH: provide a -noLagrangian option to foamToEnsight and foamToEnsightParts
for even more control.
Old code:
Found 10990 time steps
Search for moving mesh ... no moving mesh detected.
Startup in 329.09 s
Updated:
Found 10990 time steps
Search for moving mesh ... no moving mesh detected.
Startup in 1.6 s
- Cause was checking "polyMesh/points" via an IOobject.
Short-circuit with a check for a polyMesh/ directory first.
Limit the check to the master-node as well to further reduce
load on the file-system.
------------------------------
ENH: improve per-step conversion times for foamToEnsight.
Old code:
Converting 11001 time steps
Time [0] = 0 Wrote in 1.53 s
Time [1] = 1 Wrote in 1.52 s
...
Time [100] = 100 Elapsed time 205.35 s
Updated:
Converting 11001 time steps
Time [0] = 0 Wrote in 1.4 s
Time [1] = 1 Wrote in 0.07 s
...
Time [100] = 100 Elapsed time 42.4 s
- Speedup by hashing test results from the first conversion step
instead of checking each time.
Check data on all nodes to avoid problems with incomplete writes.
------------------------------
BUG: moving mesh detection failed for foamToEnsightParts
- adjusted to agree with updated foamToEnsight
------------------------------
Note:
- foamToEnsightParts (serial) still has about twice the throughput of
foamToEnsight.
- Default is a width of 8 characters, but this can be extended up to 31
characters via the '-width' command-line option.
- Now use a similar structure as foamToEnsightParts for the masking.
This reduces the clutter within the directory, makes it easier to
selectively delete some time steps (using shell commands).
- Added in a "time" information data in each sub-directory to
make it possible to reconstruct the case file with an external
script.
- Conversion of cloud data should now also work in parallel
(may need more testing).
- Support binary output for cloud data.
- Better avoidance of illegal ensight variable names.
But still partially incomplete (due to patch fields).
==================================================
Example of NEW file structure:
EnSight/verticalChannel.case # case name
EnSight/geometry # for non-moving geometry
EnSight/data/ # time-varying data
EnSight/data/00000000/
EnSight/data/00000001/
...
Fields are stored by name within the data/********/ directories:
EnSight/data/00000001/time # human-readable time info
EnSight/data/00000001/U
EnSight/data/00000001/p
...
EnSight/data/00000001/geometry # for moving geometry
Clouds are stored at the next sub-directory level:
EnSight/data/00000001/lagrangian/<cloudName>/positions
EnSight/data/00000001/lagrangian/<cloudName>/U
...
==================================================
The old structure was significantly more cluttered:
EnSight/verticalChannel.case
EnSight/verticalChannel.0000.mesh
EnSight/verticalChannel.0001.p
EnSight/verticalChannel.0001.<cloudName>
EnSight/verticalChannel.0001.<cloudName>.U
==================================================
Moved file path handling to regIOobject and made it type specific so
now every object can have its own rules. Examples:
- faceZones are now processor local (and don't search up anymore)
- timeStampMaster is now no longer hardcoded inside IOdictionary
(e.g. uniformDimensionedFields support it as well)
- the distributedTriSurfaceMesh is properly processor-local; no need
for fileModificationChecking manipulation.
foamToEnsight:
- add -noPatches option
- had incorrect part# when the internalMesh was not output
- case file is always ascii
foamToEnsightParts:
- fixed field selection bug,
no fields were selected when a single time-step was selected
