Problems with HDF5 and SWMR on network disk when program writing to the HDF5 file and program reading from the HDF5 file is running on the same host.
I’m using HDF5 library version 1.10.4 on RH7. The network disk is mounted with the NSF file system. I have also tested the same C++ code with version 1.12.0 and the issue is still there.
The issue that we experience is a significant hang (10-15 seconds) for the program writing, ones the reading program opens the output file. The writing resumes and at the end the output file is not damaged from this. New data is written to the output file every half second, hence a hang of 10-15 second is significant.
What is interesting, is that If I run the writing program on a different host that the read program (still with the same disk location), I don’t see any hang at all.
I have tried running the exact same binary files (executables and input files) on the same host but now using the /tmp disk. When I do this, I don’t see any hang.
Is this an issue that is known to HDF5 ? Have other reported this ?