[MeL/IO] Xdmf Writer without xdmf library
The OGS xdmf output algorithm depended on the XDMFLib. We experienced several problems (before).
Before:
- lack of support of 64 bit datatypes
- performance issues (slow down of about 20% of overall output time)
- multiple write accesses to xdmf
- read access to hdf file
- Bad API design (shared_ptr as part of the interface) made optimization (constexpr) impossible
Now:
- 64 bit datatypes are supported
- content of xdmf file can be accumulated in memory and written only once
- hdf file is not accessed
- switch from vtu to xdmf possible without recompiling (OGS_USE_XDMF)
- no measurable impact of xdmf writer to overall output performance!
- [0] info: [time] Output of XDMF took 0.00196958 s. (Cube 768 processes, JUWELS)