#1853: diagonal output in CarpetIOHDF5 disabled ---------------------+------------------------------------------------------ Reporter: rhaas | Owner: eschnett Type: defect | Status: new Priority: minor | Milestone: ET_2016_05 Component: Carpet | Version: development version Resolution: | Keywords: ---------------------+------------------------------------------------------
Comment (by rhaas):
It was collateral to a change that significantly reduces memory requirements for 1d,2d output in HDF5 (and likely would also in ASCII output from Carpet). The previous implementation sends the full 3d data to a single process which then extracts the lower-d data and writes it to disk. For sufficiently large grids this is very slow (significant fraction of runtime) and runs out of memory. The breaking patch fixes the issue be doing the dimensional reduction before sending data. For diagonal data the reduction is not as straightforward and was not immediately implemented.