- Lists for linear and tree communications were allocated at start-up, each of those is n^2 large where n is number of MPI ranks. This behavior leeded to job failure due to insufficient memory for large jobs.
- Only size the lists to n at the start-up. Do not allocate the memory for the list entries. Evaluate a communication list entry of type commsStruct on the fly when accessed via operator[] of the UList.

Writing parallel mesh (via renumbering the mesh by new cell numbering, using sliceMesh and writing paritionStarts) from decomposePar. (Use with flag -mesh)

(BROKEN PARALLEL IO AND RESTARTS) Writing points in vector format and removing redundant move semantics.

(BROKEN PARALLEL IO AND RESTARTS) Starting new format (TODO siceable fields) and refactoring of adios instantiation through abstract factory.

First implementation of sliceMesh conversion and initial encapsulation of ADIOS2 dependencies for writing.

- adds icoFoamTar
- installation of tar modules requires local manual third party installation (see applications/tarmodules/startTarCase/thirdParty/myreadme)
- usage of tar modules is described in applications/tarmodules/README
- example controlDict for tar modules in applications/tarmodules/tarSystemCall/controlDict
- to use ADIOS2 IO in decomposePar it has to be performed twice
    1) decomposePar -mesh
    2) decomposePar -fields
- uncollated ascii, binary, and parallel IO mode can all be started from polyMesh.bp and data.bp
(Processor folders are still created during decomposition to enable uncollated IO modes.)

- ADIOS restricts the string size (64kB?) and thus e.g. faces could not be written
- Switch from std::string to char arrays
- Reading with bpls is still possible with -S flag, e.g.:
  bpls -Sd constant/polyMesh.bp constant/polyMesh/faces

- ADIOS Mesh data is written and read to/from "constant/polyMesh.bp"
- When reading such functions such headerOkPar, findInstance or parStreamPar check first whether data.bp or polyMesh.bp are present

- Exclude some solvers and schemes not needed for basic runs

- Add a functionality to UListIO for writing non-contiguous data in order to handle faces (list of lists)
- UListIO uses a OStringStream to buffer list of lists and OFStream puts it as a string into the .bp file at destruction
- Make a typedef parIOType for the ADIOS data type which are not strings. Now it can be changed (e.g. from char to double) at one place in IOStream.H

 - added libraries blockMesh relies on:
   - src/ODE excluding sixDOF
   - src/dynamicMesh/dynamicMesh
   - src/mesh/blockMesh

- Hack BeginStep/EndStep into regIOobject using static member functions. Allows to Put variables in Deffered Mode.
- Somewhat ugly solution, but enables proper benchmarking.
- Since Mode::Append has a bug (no aggregation possible) on ADIOS side, the default mode for writing is set to Mode::Write.

- Check if data.bp is present. If yes, read from it. If not, fall back to standard IO.

    - The only working variant for write is BeginStep() and EndStep() in Mode::Append. Other variants of writing have issues, see commentary in adiosWrite.C
    - Save only double arrays => all adios templates are instantiated with double* instead of char*.
    - Refactor adios classes. Pull adios write and read functionality out of adiosCore into seprate classes. Clean up.

Example of a subdict in controlDict:

DebugSwitches
{
    dictionary 2;
    IOobject 1;
    time 1;
    DebugIOList 1;
    DebugIOField 1;
    volScalarField 1;
    volVectorField 1;
    OFstream 1;
    ISstream 2;
    IFstream 1;
}

Note that some of the switches have several level of verbosity, i.e. much more ouput if set to 2.

Required to have multiple writes without overwriting.
Plus, new placement of ADIOS2 file in case folder.

Replaces previous data split.

- The id consists now of the relative path to the file and the keyword / block name.
- Every keyword given to an OFstream object lands in the LIFO stack. This means that the internalField id is available when needed.
- The stack is poped if a token::END_STATEMENT is seen by the OFstream object.

Usage:
- Set environment with WM_THIRD_PARTY_ADIOS2_271=1 (see also etc/bashrc)
- Compile with Allwmake.firstInstall

The minimal example of an ADIOS2 interface in foam/db/IOstreams/A2streams illustrates linking against the extended ThirdParty.

- Transfer the block name from UListIO to OFsteam if indent is incremented and keep it in a LIFO stack.
- Pop LIFO stack if indent is decremented.
- Get the identifier from OFstream via getBlockId().

To turn on debug output put a DebugSwitch dict into controlDict, e.g.:

DebugSwitches
{
    OFstream 0;
    IOobject 0;
    regIOobject 0;
    objectRegistry 0;
    time 0;
    DebugIOUList 1;
    DebugIODimensionedField 0;
    DebugIOField 0;
    Ostream 2;
    OSstream 1;
}

Note that the switches may have a value higher than 1 to allow more output.

IO split of writing binary data into separate file. Activate with 'writeFormat parallel' in controlDict.