- remove unused/unusable broadcast stream constructors/methods
- provide OPBstream::sends() and IPBstream::recvs() methods,
refactored from Pstream::broadcasts. These will always use
serializations, even for contiguous content.
- additional methods to support special handling of zero-sized lists.
For example,
if (UPstream::master(comm))
{
if (list.empty()) OPBstream::send(Foam::zero, comm);
else OPBstream::send(list, comm);
}
else
{
IPBstream is(comm);
if (is.remaining()) { is >> list; }
else { list.clear(); }
}
This avoids serialization of an empty list and the resulting double
broadcast (size + content), using instead a single broadcast (size).
STYLE: more consistency in communicator types (int vs label)
- allows construction of string tokens holding character content.
For example, data that has been serialized and buffered and that
now needs to be written or sent to another process.
- change write(const string&) to write(const std::string&).
This allows output of std::string without an intermediate copy.
- additional writeQuoted method to handle range of char data:
writeQuoted(const char* str, std::streamsize len, bool)
This helps with supporting string_view and span<char>
- add operator<< for stdFoam::span<char> and std::string_view (c++17)
- avoid duplicate code in OBJstream
STYLE: add override keyword for IO stream methods
- the construction of compound tokens is now split into two stages:
- default construct
- read contents
This permits a larger variety of handling.
- the new token::readCompoundToken(..) method allows for simpler
more failsafe invocations.
- forward resize(), read() methods for compound tokens to support
separate read and population.
Top-level refCompoundToken() method for modify access.
ENH: split off a private readCompoundToken() method within ISstream
- this allows overloading and alternative tokenisation handling for
derived classes
- with C++11, static constexpr variables apparently also require
definition in a translation unit and not just as inlined quantities.
Mostly not an issue, however gcc with -O0 does not do the inlining
and thus actually requires them to be defined in a translation unit
as well.
These variables were provided for symmetry with worldComm, but only
used in low-level internal code. Changing to inlined functions
solves the linkage issue and also aligns with the commWorld()
function naming.
Mnemonics:
MPI_COMM_SELF => UPstream::commSelf()
overall MPI_COMM_WORLD => UPstream::commGlobal(), sometimes commWorld()
local COMM_WORLD => UPstream::commWorld()
- have read(nullptr, count) and readRaw(nullptr, count) act like a
forward seek instead of failing.
This lets it be used to advance through a file without needing to
allocate (and discard) storage space etc.
- allows the possibility of using demand-driven internal buffers
and/or different storage mechanisms.
Changes:
* old: sendBuf_[proci] -> accessSendBuffer(proci)
* old: recvBuf_[proci] -> accessRecvBuffer(proci)
* old: recvBufPos_[proci] -> accessRecvPosition(proci)
only affects internals of UIPstreamBase and UOPstreamBase
BUG: reduceOr in PstreamBuffers uses world communicator
- should respect the value of the communicator defined within
PstreamBuffers
- UPstream::Request wrapping class provides an opaque wrapper for
vendor MPI_Request values, independent of global lists.
ENH: support for MPI barrier (blocking or non-blocking)
ENH: support for MPI sync-send variants
STYLE: deprecate waitRequests() without a position parameter
- in many cases this can indicate a problem in the program logic since
normally the startOfRequests should be tracked locally.
- with IOstreamOption there are no cases where we need to construct
top-level streams (eg, IFstream, OFstream) with additional information
about the internal IOstream 'version' (eg, version: 2.0).
Makes it more convenient to open files with a specified
format/compression combination - no clutter of specifying the
version
- consistent with defining IO of int32_t/int64_t and with recent
changes to ensightFile. Using the primitives directly instead of
typedefs to them makes the code somewhat less opaque.
STYLE: qualify format/version/compression with IOstreamOption not IOstream
STYLE: reduce number of lookups when scanning {fa,fv}Solution
STYLE: call IOobject::writeEndDivider as static
- PstreamBuffers nProcs() and allProcs() methods to recover the rank
information consistent with the communicator used for construction
- allowClearRecv() methods for more control over buffer reuse
For example,
pBufs.allowClearRecv(false);
forAll(particles, particlei)
{
pBufs.clear();
fill...
read via IPstream(..., pBufs);
}
This preserves the receive buffers memory allocation between calls.
- finishedNeighbourSends() method as compact wrapper for
finishedSends() when send/recv ranks are identically
(eg, neighbours)
- hasSendData()/hasRecvData() methods for PstreamBuffers.
Can be useful for some situations to skip reading entirely.
For example,
pBufs.finishedNeighbourSends(neighProcs);
if (!returnReduce(pBufs.hasRecvData(), orOp<bool>()))
{
// Nothing to do
continue;
}
...
On an individual basis:
for (const int proci : pBufs.allProcs())
{
if (pBufs.hasRecvData(proci))
{
...
}
}
Also conceivable to do the following instead (nonBlocking only):
if (!returnReduce(pBufs.hasSendData(), orOp<bool>()))
{
// Nothing to do
pBufs.clear();
continue;
}
pBufs.finishedNeighbourSends(neighProcs);
...
- a somewhat specialized use case, but can be useful when there are
many ranks with sparse communication but for which the access
pattern is established during inner loops.
PstreamBuffers pBufs(Pstream::commsTypes::nonBlocking);
pBufs.allowClearRecv(false);
PtrList<OPstream> output(Pstream::nProcs());
while (condition)
{
// Rewind existing streams
forAll(output, proci)
{
auto* osptr = output.get(proci);
if (osptr)
{
(*osptr).rewind();
}
}
for (Particle& p : myCloud)
{
label toProci = ...;
// Get or create output stream
auto* osptr = output.get(toProci);
if (!osptr)
{
osptr = new OPstream(toProci, pBufs);
output.set(toProci, osptr);
}
// Append more data...
(*osptr) << p;
}
pBufs.finishedSends();
... reads
}
- refactor as an MPI-independent base class.
Add bufferIPC{send,recv} private methods for construct/destruct.
Eliminates code duplication from two constructor forms and reduces
additional constructor definitions in dummy library.
- add PstreamBuffers access methods, refactor common finish sends
code, tweak member packing
ENH: resize_nocopy for processorLduInterface buffers
- content is immediately overwritten
STYLE: cull unneeded includes in processorFa*
- handled by processorLduInterface
