ENH: support transfer from a wrapped MPI request to global list
- allows coding with a list UPstream::Request and subsequently either
retain that list or transfer into the global list.
- simplifies communication structuring with intra-host communication.
Can be used for IO only, or for specialised communication.
Demand-driven construction. Gathers the SHA1 of host names when
determining the connectivity. Internally uses an MPI_Gather of the
digests and a MPI_Bcast of the unique host indices.
NOTE:
does not use MPI_Comm_splt or MPI_Comm_splt_type since these
return MPI_COMM_NULL on non-participating process which does not
easily fit into the OpenFOAM framework.
Additionally, if using the caching version of
UPstream::commInterHost() and UPstream::commIntraHost()
the topology is determined simultaneously
(ie, equivalent or potentially lower communication).
- make sizing of commsStruct List demand-driven as well
for more robustness, fewer unneeded allocations.
- fix potential latent bug with allBelow/allNotBelow for proc 0
(linear communication).
ENH: remove unused/unusable UPstream::communicator optional parameter
- had constructor option to avoid constructing the MPI backend,
but this is not useful and inconsistent with what the reset or
destructor expect.
STYLE: local use of UPstream::communicator
- automatically frees communicator when it leaves scope
- these are primarily when encountering sparse (eg, inter-host)
communicators. Additional UPstream convenience methods:
is_rank(comm)
=> True if process corresponds to a rank in the communicators.
Can be a master rank or a sub-rank.
is_parallel(comm)
=> True if parallel algorithm or exchange is used on the process.
same as
(parRun() && (nProcs(comm) > 1) && is_rank(comm))
- replace the "one-size-fits-all" approach of tensor field inv()
with individual 'failsafe' inverts.
The inv() field function historically just checked the first entry
to detect 2D cases and adjusted/readjusted *all* tensors accordingly
(to avoid singularity tensors and/or noisy inversions).
This seems to have worked reasonably well with 3D volume meshes, but
breaks down for 2D area meshes, which can be axis-aligned
differently on different sections of the mesh.
- not currently used, but it is possible that communicator allocation
modifies the list of sub-ranks. Ensure that the correct size is used
when (re)initialising the linear/tree structures.
STYLE: adjust MPI test applications
- remove some clutter and unneeded grouping.
Some ideas for host-only communicators
- attributes such as assignable(), coupled() etc
- common patchField types: calculatedType(), zeroGradientType() etc.
This simplifies reference to these types without actually needing a
typed patchField version.
ENH: add some basic patchField types to fieldTypes namespace
- allows more general use of the names
ENH: set extrapolated/calculated from patchInternalField directly
- avoids intermediate tmp
- for cases where a 3D tensor is being used to represent 2D content,
the determinant is zero. Can use inv2D(excludeDirection) to compensate
and invert as if it were only 2D.
ENH: consistent definitions for magSqr of symmTensors, diagSqr() norm
COMP: return scalar not component type for magSqr
- had inconsistent definitions with SymmTensor returning the component
type and Tensor returning scalar. Only evident with complex.
- similar to UPstream::parRun(), the setter returns the previous value.
The accessors are prefixed with 'comm':
Eg, commGlobal(), commWarn(), commWorld(), commSelf().
This distinguishes them from any existing variables (eg, worldComm)
and arguably more similar to MPI_COMM_WORLD etc...
If demand-driven communicators are added in the future, the function
call syntax can help encapsulate that.
Previously:
const label oldWarnComm = UPstream::warnComm;
const label oldWorldComm = UPstream::worldComm;
UPstream::warnComm = myComm;
UPstream::worldComm = myComm;
...
UPstream::warnComm = oldWarnComm;
UPstream::worldComm = oldWorldComm;
Now:
const label oldWarnComm = UPstream::commWarn(myComm);
const label oldWorldComm = UPstream::commWorld(myComm);
...
UPstream::commWarn(oldWarnComm);
UPstream::commWorld(oldWorldComm);
STYLE: check (warnComm >= 0) instead of (warnComm != -1)
- useful when regular contents are to be read via an IOobject and
returned.
Eg, dictionary propsDict(IOdictionary::readContents(dictIO));
vs. dictionary propsDict(static_cast<dictionary&&>(IOdictionary(dictIO)));
Commonly these would have simply been constructed directly as the
IO container:
eg, IOdictionary propsDict(dictIO);
However, that style may not ensure proper move semantics for return
types.
Now,
=====
labelList decomp(labelIOList::readContents(io));
... something
return decomp;
=====
Previously,
=====
labelIOList decomp(io);
// Hope for the best...
return decomp;
// Or be explicit and ensure elision occurs...
return labelList(std::move(static_cast<labelList&>(decomp)));
=====
Note:
labelList list(labelIOList(io));
looks like a good idea, but generally fails to compile
- the iterator/const_iterator now skip any nullptr entries,
which enables the following code to work even if the PtrList
contains nullptr:
for (const auto& intf : interfaces)
{
// Do something
...
}
- this is a change in behaviour compared to OpenFOAM-v2212 and earlier,
but is non-breaking:
* Lists without null entries will traverse exactly as before.
* Lists with null entries will now traverse correctly without
provoking a FatalError.
- allows unambiguous of count() for other classes.
Naming as per std::shared_ptr.
STYLE: qualify use_count() and unique() methods with the refCount base
- clearer/consistent meaning
- the null output adapter was previously used for the HashTables API
when HashSet actually stored key/value. Now that the node only
contains the key, having suppressed output is redundant, as is the
zero::null class (reduces clutter)
STYLE: replace one::minus dispatch in extendedEdgeMesh
GIT: remove Foam::nil typedef (deprecated since May-2017)
ENH: add pTraits and IO for std::int8_t
STYLE: cull some implicitly available includes
- pTraits.H is included by label/scalar etc
- zero.H is included by UList
STYLE: cull redundant forward declarations for Istream/Ostream
- in earlier versions: used 'fixed' notation
to force floating point numbers to be printed with at least
some decimal digits. However, in the meantime we are more
flexible with handling float/int input so remove this constraint.
- use ITstream::toString, which makes the string expansion of ${var}
and the expression expansion of $[var] consistent.
- defined for lerp between two fields,
either with a constant or a field of interpolation factors.
* plain Field, DimensionedField, FieldField, GeometricFields
- using a field to lerp between two constants is not currently
supported
- this is slightly longer to write (but consistent with clamp_min
etc). The main reason is that this allows easier use of the clamp()
free function.
STYLE: skip checks for bad/invalid clamping ranges
- ranges are either already validated before calling, the caller logic
has already made the branching decision.
- in most cases can simply construct mapDistribute with the sendMap
and have it take care of communication and addressing for the
corresponding constructMap.
This removes code duplication, which in some cases was also using
much less efficient mechanisms (eg, combineReduce on list of
lists, or an allGatherList on the send sizes etc) and also
reduces the number of places where Pstream::exchange/exchangeSizes
is being called.
ENH: reduce communication in turbulentDFSEMInlet
- was doing an allGatherList to populate a mapDistribute.
Now simply use PstreamBuffers mechanisms directly.
- dynamic sparse data exchange using Map to hold data and sizes.
Still uses the personalised exchange paradigm, but with non-blocking
consensus exchange to obtain the sizes and regular point-to-point
for the data exchange itself. This avoids an all-to-all but still
keeps the point-to-point for overlapping communication, data
chunking etc.
- basic functionality similar to std::span (C++20).
Holds pointer and size: for lightweight handling of address ranges.
- implements cdata_bytes() and data_bytes() methods for similarity
with UList. For span, however, both container accesses are const
but the data_bytes() method is only available when the
underlying pointer is non-const.
No specializations of std::as_bytes() or std::as_writeable_bytes()
as free functions, since std::byte etc are not available anyhow.
- name and functionality similar to std::unordered_map (C++17).
Formalizes what had been previously been implemented in IOobjectList
but now manages without pointer deletion/creation.
- waits for completion of any of the listed requests and returns the
corresponding index into the list.
This allows, for example, dispatching of data when the receive is
completed.
- permits distinction between communicators/groups that were
user-created (eg, MPI_Comm_create) versus those queried from MPI.
Previously simply relied on non-null values, but that is too fragile
ENH: support List<Request> version of UPstream::finishedRequests
- allows more independent algorithms
ENH: added UPstream::probeMessage(...). Blocking or non-blocking
- previously built the entire adjacency table (full communication!)
but this is only strictly needed when using 'scheduled' as the
default communication mode. For blocking/nonBlocking modes this
information is not necessary at that point.
The processorTopology::New now generally creates a smaller amount of
data at startup: the processor->patch mapping and the patchSchedule.
If the default communication mode is 'scheduled', the behaviour is
almost identical to previously.
- Use Map<label> for the processor->patch mapping for a smaller memory
footprint on large (ie, sparsely connected) cases. It also
simplifies coding and allows recovery of the list of procNeighbours
on demand.
- Setup the processor initEvaluate/evaluate states with fewer loops
over the patches.
========
BREAKING: procNeighbours() method changed definition
- this was previously the entire adjacency table, but is now only the
processor-local neighbours. Now use procAdjacency() to create or
recover the entire adjacency table.
The only known use is within Cloud<ParticleType>::move and there it
was only used to obtain processor-local information.
Old:
const labelList& neighbourProcs =
mesh.globalData().topology().procNeighbours()[Pstream::myProcNo()];
New:
const labelList& neighbourProcs =
mesh.globalData().topology().procNeighbours();
// If needed, the old definition (with communication!)
const labelListList& connectivity =
mesh.globalData().topology().procAdjacency();
- vector, tensor versions are defined component-wise
to avoid intermediates.
The base version uses the form "(1-t)*a + t*b" without any bounds
checking (ie, will also extrapolate).
- proper component-wise clamping for MinMax clamp().
- construct clampOp from components
- propagate clamp() method from GeometricField to FieldField and Field
- clamp_min() and clamp_max() for one-sided clamping,
as explicit alternative to min/max free functions which can
be less intuitive and often involve additional field copies.
- top-level checks to skip applying invalid min/max ranges
and bypass the internal checks of MinMax::clamp() etc.
