when building the version number is automatically injected into a header now. This allows for more certainty as to what GF version is being used. Note that this is disabled when building the python wheel as there is no clear way to map this dynamically generated header into the wheel structure. This is however not an issue as the python module has a seperate __version__ variable.
Major work on spectral solver, can now evolve up to about a year. At
that point we likely need to impliment repartitioning logic to stabalize
the network or some other scheme based on the jacobian structure
Previously engines were not thread safe, a seperate engine would be
needed for every thread. This is no longer the case. This allows for
much more efficient parallel execution
More preformance improvmnets
1. Switch to mimalloc which gave a roughly 10% improvment accross the
board
2. Use much faster compososition caching
3. Reusing work vector
Added more agressive caching, regained about another 50% performance gain. Solar model over 10Gyr now takes roughly 400ms (as opposed to 1 second before)
Previously there was a bug where some reverse reactions were being
classed as forward reactions. This results in a failure of many
timesteps due to the reverse reactions very high molar flows
Previously QSE solving was done using Eigen. While this worked we were
limited in the ability to use previous iterations to speed up later
steps. We have switched to KINSOL, from SUNDIALS, for linear solving.
This has drastically speed up the process of solving for QSE abundances,
primarily because the jacobian matrix does not need to be generated
every single time time a QSE abundance is requested.
This entailed a major rewrite of the composition handling from each engine and engine view along with the solver and primer. The intent here is to let Compositions be constructed from the same extensive property which the solver tracks internally. This addressed C0 discontinuity issues in the tracked molar abundances of species which were introduced by repeadidly swaping from molar abundance space to mass fraction space and back. This also allowed for a simplification of the primeNetwork method. Specifically the mass borrowing system was dramatically simplified as molar abundances are extensive.
previousl the sparsity calculations for the jacobian matrix were completly broken. The method subgraph_sparsity was returning that all derivities were only depenednt on temperature and density. It should have been reporting that they also depended on some of the abundances. This was resolved by switching to a different structural sparsity engine (for_jac_sparsity). This bug had turned the solver into a fixed point iteration solver which failed for the stiff system we have. Now that it is resolved the solver can once again evolved over Gyr timescales.
essentially all callers can now inform the graph engine about which species they hold active and graph engine then uses those to define a sparsity pattern and only calculate the jacobian along that sparsity pattern
bigs were introduced by the interface change from accepting raw molar abundance vectors to using the composition vector. This commit resolves many of these, including preformant ways to report that a species is not present in the composition and unified index lookups using composition object tooling.
BREAKING CHANGE:
Major weak rate progress which includes: A refactor of many of the public interfaces for GridFire Engines to use composition objects as opposed to raw abundance vectors. This helps prevent index mismatch errors. Further, the weak reaction class has been expanded with the majority of an implimentation, including an atomic_base derived class to allow for proper auto diff tracking of the interpolated table results. Some additional changes are that the version of fourdst and libcomposition have been bumped to versions with smarter caching of intermediate vectors and a few bug fixes.
