Growing memory usage when opening and closing certain netcdf-files

[planetMDX]

version netcdf: 4.9.0
OS: macos Ventura
compiler: Apple clang version 14.0.0 (clang-1400.0.29.202)
opening certain netcdf-files and closing them allocates memory without deallocating said memory when closing those files.

From https://www.unidata.ucar.edu/software/netcdf/examples/files.html only test_echam_spectral-deflated.nc, OMI-Aura_L2-example.nc and test_hgroups.nc show this behaviour.

Sample-code:

#include <netcdf.h>
#include <stdlib.h>
#include <stdio.h>
int main()
{
    setenv("HDF5_USE_FILE_LOCKING", "FALSE", 1);
    while (1)
    {
        int nid = 0;
        nc_open("/path/to/file/OMI-Aura_L2-example.nc", 0, &nid);
        nc_close(nid);
    }
    return 0;
}

after about 10 min I had about 65MiB heap usage according to the XCode-profiler.

[DennisHeimbigner]

What version of HDF5 are you using?

[DennisHeimbigner]

Also, do you have some equivalent of valgrind that you can run? Perhaps
clang on Max has the sanitizer flag?

[planetMDX]

What version of HDF5 are you using?

1.12.2

I have done the same on my arch linux machine with netcdf 4.9.0-3 and hdf5 1.12.2-1 with a limited amount of loop repetitions: 10^6 results in a memory size of 385 MiB and 10^4 repetitions results in 57.1 MiB.
Valgrinding the 10^4 repetions with valgrind --leak-check=full --show-reachable=yes resulted in
repetions10000.
Running valgrind with the same options on the infinite loop and interrupting after ~1h results in this output: resultsInfinteInteruppted.

[planetMDX]

this should be caused by #2723 and HDFGroup/hdf5#3396, of which the issue on the netcdf side is fixed.