There it is.
> DATASET "BSE_RESONANT_COMPRESSED1_DONE" {
> DATATYPE H5T_STRING {
> STRSIZE 1;
> STRPAD H5T_STR_NULLTERM;
> CSET H5T_CSET_UTF8;
> CTYPE H5T_C_S1;
Your char arrays are being stored as strings, not 1-byte characters. This
incurs overhead for each character. I am not familiar with the exact
details of physical storage of HDF5 strings, but it doesn't matter.
This scheme is inefficient, and you should find something better.
I vaguely recall some changes in netcdf-4 character storage in recent
years. Since you are using an older version of the netcdf library, first
try the latest version. Otherwise, as I said elsewhere, go to 64-bit or
CDF5 formats.
If netcdf-4 is important to you for some reason, you might also consider
encoding your char data into signed or unsigned bytes.
On Sat, May 2, 2020 at 10:38 AM Davide Sangalli <davide.sangalli@xxxxxx>
wrote:
> h5stat -Ss ndb.BS_COMPRESS0.005000_Q1
>
> Filename: ndb.BS_COMPRESS0.005000_Q1
> Free-space section threshold: 1 bytes
> Small size free-space sections (< 10 bytes):
> Total # of small size sections: 0
> Free-space section bins:
> Total # of sections: 0
> File space management strategy: H5F_FILE_SPACE_ALL
> Summary of file space information:
> File metadata: 4355 bytes
> Raw data: 16356758312 bytes
> Amount/Percent of tracked free space: 0 bytes/0.0%
> Unaccounted space: 6216 bytes
> Total space: 16356768883 bytes
>
>
>
> On Sat, May 2, 2020 at 6:28 PM +0200, "Davide Sangalli" <
> davide.sangalli@xxxxxx> wrote:
>
> h5dump -Hp ndb.BS_COMPRESS0.005000_Q1
>> HDF5 "ndb.BS_COMPRESS0.005000_Q1" {
>> GROUP "/" {
>> ATTRIBUTE "_NCProperties" {
>> DATATYPE H5T_STRING {
>> STRSIZE 57;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> }
>> DATASET "BSE_RESONANT_COMPRESSED1" {
>> DATATYPE H5T_IEEE_F32LE
>> DATASPACE SIMPLE { ( 24776792, 2 ) / ( 24776792, 2 ) }
>> STORAGE_LAYOUT {
>> CONTIGUOUS
>> SIZE 198214336
>> OFFSET 16158554547
>> }
>> FILTERS {
>> NONE
>> }
>> FILLVALUE {
>> FILL_TIME H5D_FILL_TIME_IFSET
>> VALUE 9.96921e+36
>> }
>> ALLOCATION_TIME {
>> H5D_ALLOC_TIME_EARLY
>> }
>> ATTRIBUTE "DIMENSION_LIST" {
>> DATATYPE H5T_VLEN { H5T_REFERENCE { H5T_STD_REF_OBJECT }}
>> DATASPACE SIMPLE { ( 2 ) / ( 2 ) }
>> }
>> }
>> DATASET "BSE_RESONANT_COMPRESSED1_DONE" {
>> DATATYPE H5T_STRING {
>> STRSIZE 1;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_UTF8;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SIMPLE { ( 2025000000 ) / ( 2025000000 ) }
>> STORAGE_LAYOUT {
>> CONTIGUOUS
>> SIZE 2025000000
>> OFFSET 8100002379
>> }
>> FILTERS {
>> NONE
>> }
>> FILLVALUE {
>> FILL_TIME H5D_FILL_TIME_IFSET
>> VALUE ""
>> }
>> ALLOCATION_TIME {
>> H5D_ALLOC_TIME_EARLY
>> }
>> ATTRIBUTE "DIMENSION_LIST" {
>> DATATYPE H5T_VLEN { H5T_REFERENCE { H5T_STD_REF_OBJECT }}
>> DATASPACE SIMPLE { ( 1 ) / ( 1 ) }
>> }
>> }
>> DATASET "BSE_RESONANT_COMPRESSED2_DONE" {
>> DATATYPE H5T_STRING {
>> STRSIZE 1;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_UTF8;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SIMPLE { ( 2025000000 ) / ( 2025000000 ) }
>> STORAGE_LAYOUT {
>> CONTIGUOUS
>> SIZE 2025000000
>> OFFSET 10125006475
>> }
>> FILTERS {
>> NONE
>> }
>> FILLVALUE {
>> FILL_TIME H5D_FILL_TIME_IFSET
>> VALUE ""
>> }
>> ALLOCATION_TIME {
>> H5D_ALLOC_TIME_EARLY
>> }
>> ATTRIBUTE "DIMENSION_LIST" {
>> DATATYPE H5T_VLEN { H5T_REFERENCE { H5T_STD_REF_OBJECT }}
>> DATASPACE SIMPLE { ( 1 ) / ( 1 ) }
>> }
>> }
>> DATASET "BSE_RESONANT_COMPRESSED3_DONE" {
>> DATATYPE H5T_STRING {
>> STRSIZE 1;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_UTF8;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SIMPLE { ( 781887360 ) / ( 781887360 ) }
>> STORAGE_LAYOUT {
>> CONTIGUOUS
>> SIZE 781887360
>> OFFSET 15277557963
>> }
>> FILTERS {
>> NONE
>> }
>> FILLVALUE {
>> FILL_TIME H5D_FILL_TIME_IFSET
>> VALUE ""
>> }
>> ALLOCATION_TIME {
>> H5D_ALLOC_TIME_EARLY
>> }
>> ATTRIBUTE "DIMENSION_LIST" {
>> DATATYPE H5T_VLEN { H5T_REFERENCE { H5T_STD_REF_OBJECT }}
>> DATASPACE SIMPLE { ( 1 ) / ( 1 ) }
>> }
>> }
>> DATASET "BS_K_compressed1" {
>> DATATYPE H5T_IEEE_F32BE
>> DATASPACE SIMPLE { ( 24776792 ) / ( 24776792 ) }
>> STORAGE_LAYOUT {
>> CONTIGUOUS
>> SIZE 99107168
>> OFFSET 16059447379
>> }
>> FILTERS {
>> NONE
>> }
>> FILLVALUE {
>> FILL_TIME H5D_FILL_TIME_IFSET
>> VALUE H5D_FILL_VALUE_DEFAULT
>> }
>> ALLOCATION_TIME {
>> H5D_ALLOC_TIME_EARLY
>> }
>> ATTRIBUTE "CLASS" {
>> DATATYPE H5T_STRING {
>> STRSIZE 16;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> }
>> ATTRIBUTE "NAME" {
>> DATATYPE H5T_STRING {
>> STRSIZE 64;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> }
>> ATTRIBUTE "REFERENCE_LIST" {
>> DATATYPE H5T_COMPOUND {
>> H5T_REFERENCE { H5T_STD_REF_OBJECT } "dataset";
>> H5T_STD_I32LE "dimension";
>> }
>> DATASPACE SIMPLE { ( 1 ) / ( 1 ) }
>> }
>> }
>> DATASET "BS_K_linearized1" {
>> DATATYPE H5T_IEEE_F32BE
>> DATASPACE SIMPLE { ( 2025000000 ) / ( 2025000000 ) }
>> STORAGE_LAYOUT {
>> CONTIGUOUS
>> SIZE 8100000000
>> OFFSET 2379
>> }
>> FILTERS {
>> NONE
>> }
>> FILLVALUE {
>> FILL_TIME H5D_FILL_TIME_IFSET
>> VALUE H5D_FILL_VALUE_DEFAULT
>> }
>> ALLOCATION_TIME {
>> H5D_ALLOC_TIME_EARLY
>> }
>> ATTRIBUTE "CLASS" {
>> DATATYPE H5T_STRING {
>> STRSIZE 16;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> }
>> ATTRIBUTE "NAME" {
>> DATATYPE H5T_STRING {
>> STRSIZE 64;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> }
>> ATTRIBUTE "REFERENCE_LIST" {
>> DATATYPE H5T_COMPOUND {
>> H5T_REFERENCE { H5T_STD_REF_OBJECT } "dataset";
>> H5T_STD_I32LE "dimension";
>> }
>> DATASPACE SIMPLE { ( 2 ) / ( 2 ) }
>> }
>> }
>> DATASET "BS_K_linearized2" {
>> DATATYPE H5T_IEEE_F32BE
>> DATASPACE SIMPLE { ( 781887360 ) / ( 781887360 ) }
>> STORAGE_LAYOUT {
>> CONTIGUOUS
>> SIZE 3127549440
>> OFFSET 12150006475
>> }
>> FILTERS {
>> NONE
>> }
>> FILLVALUE {
>> FILL_TIME H5D_FILL_TIME_IFSET
>> VALUE H5D_FILL_VALUE_DEFAULT
>> }
>> ALLOCATION_TIME {
>> H5D_ALLOC_TIME_EARLY
>> }
>> ATTRIBUTE "CLASS" {
>> DATATYPE H5T_STRING {
>> STRSIZE 16;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> }
>> ATTRIBUTE "NAME" {
>> DATATYPE H5T_STRING {
>> STRSIZE 64;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> }
>> ATTRIBUTE "REFERENCE_LIST" {
>> DATATYPE H5T_COMPOUND {
>> H5T_REFERENCE { H5T_STD_REF_OBJECT } "dataset";
>> H5T_STD_I32LE "dimension";
>> }
>> DATASPACE SIMPLE { ( 1 ) / ( 1 ) }
>> }
>> }
>> DATASET "complex" {
>> DATATYPE H5T_IEEE_F32BE
>> DATASPACE SIMPLE { ( 2 ) / ( 2 ) }
>> STORAGE_LAYOUT {
>> CONTIGUOUS
>> SIZE 8
>> OFFSET 16059447371
>> }
>> FILTERS {
>> NONE
>> }
>> FILLVALUE {
>> FILL_TIME H5D_FILL_TIME_IFSET
>> VALUE H5D_FILL_VALUE_DEFAULT
>> }
>> ALLOCATION_TIME {
>> H5D_ALLOC_TIME_EARLY
>> }
>> ATTRIBUTE "CLASS" {
>> DATATYPE H5T_STRING {
>> STRSIZE 16;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> }
>> ATTRIBUTE "NAME" {
>> DATATYPE H5T_STRING {
>> STRSIZE 64;
>> STRPAD H5T_STR_NULLTERM;
>> CSET H5T_CSET_ASCII;
>> CTYPE H5T_C_S1;
>> }
>> DATASPACE SCALAR
>> }
>> ATTRIBUTE "REFERENCE_LIST" {
>> DATATYPE H5T_COMPOUND {
>> H5T_REFERENCE { H5T_STD_REF_OBJECT } "dataset";
>> H5T_STD_I32LE "dimension";
>> }
>> DATASPACE SIMPLE { ( 1 ) / ( 1 ) }
>> }
>> }
>> }
>> }
>>
>>
>>
>> On Sat, May 2, 2020 at 5:55 PM +0200, "Wei-Keng Liao" <
>> wkliao@xxxxxxxxxxxxxxxx> wrote:
>>
>> For HDF5 files, command “h5dump -Hp ndb.BS_COMPRESS0.005000_Q1” shows
>>> the data chunk settings used by all datasets in the file.
>>>
>>> Command “h5stat -Ss ndb.BS_COMPRESS0.005000_Q1” shows information about
>>> free space, metadata, raw data, etc.
>>>
>>> They may reveal why your file is abnormal big.
>>> Most likely it is the chunk setting you used.
>>>
>>> Wei-keng
>>>
>>> > On May 1, 2020, at 6:40 PM, Davide Sangalli wrote:
>>> >
>>> > I also add
>>> >
>>> > ncvalidator ndb.BS_COMPRESS0.005000_Q1
>>> > Error: Unknow file signature
>>> > Expecting "CDF1", "CDF2", or "CDF5", but got "�HDF"
>>> > File "ndb.BS_COMPRESS0.005000_Q1" fails to conform with CDF file format
>>> > specifications
>>> >
>>> > Best,
>>> > D.
>>> >
>>> > On 02/05/20 01:26, Davide Sangalli wrote:
>>> >> Output of ncdump -hs
>>> >>
>>> >> D.
>>> >>
>>> >> ncdump -hs BSK_2-5B_X59RL-50B_SP_bse-io/ndb.BS_COMPRESS0.005000_Q1
>>> >>
>>> >> netcdf ndb.BS_COMPRESS0 {
>>> >> dimensions:
>>> >> BS_K_linearized1 = 2025000000 ;
>>> >> BS_K_linearized2 = 781887360 ;
>>> >> complex = 2 ;
>>> >> BS_K_compressed1 = 24776792 ;
>>> >> variables:
>>> >> char BSE_RESONANT_COMPRESSED1_DONE(BS_K_linearized1) ;
>>> >> BSE_RESONANT_COMPRESSED1_DONE:_Storage = "contiguous" ;
>>> >> char BSE_RESONANT_COMPRESSED2_DONE(BS_K_linearized1) ;
>>> >> BSE_RESONANT_COMPRESSED2_DONE:_Storage = "contiguous" ;
>>> >> char BSE_RESONANT_COMPRESSED3_DONE(BS_K_linearized2) ;
>>> >> BSE_RESONANT_COMPRESSED3_DONE:_Storage = "contiguous" ;
>>> >> float BSE_RESONANT_COMPRESSED1(BS_K_compressed1, complex) ;
>>> >> BSE_RESONANT_COMPRESSED1:_Storage = "contiguous" ;
>>> >> BSE_RESONANT_COMPRESSED1:_Endianness = "little" ;
>>> >> // global attributes:
>>> >> :_NCProperties =
>>> >> "version=1|netcdflibversion=4.4.1.1|hdf5libversion=1.8.18" ;
>>> >> :_SuperblockVersion = 0 ;
>>> >> :_IsNetcdf4 = 1 ;
>>> >> :_Format = "netCDF-4" ;
>>> >>
>>> >>
>>> >>
>>> >> On Sat, May 2, 2020 at 12:24 AM +0200, "Dave Allured - NOAA Affiliate"
>>> >> wrote:
>>> >>
>>> >> I agree that you should expect the file size to be about 1 byte per
>>> >> stored character. IMO the most likely explanation is that you have a
>>> >> netcdf-4 file with inappropriately small chunk size. Another
>>> >> possibility is a 64-bit offset file with crazy huge padding between file
>>> >> sections. This is very unlikely, but I do not know what
>>> >> is inside your writer code.
>>> >>
>>> >> Diagnose, please. Ncdump -hs. If it is 64-bit offset, I think
>>> >> ncvalidator can display the hidden pad sizes.
>>> >>
>>> >>
>>> >> On Fri, May 1, 2020 at 3:37 PM Davide Sangalli wrote:
>>> >> Dear all,
>>> >> I'm a developer of a fortran code which uses netcdf for I/O
>>> >>
>>> >> In one of my runs I created a file with some huge array of characters.
>>> >> The header of the file is the following:
>>> >> netcdf ndb.BS_COMPRESS0 {
>>> >> dimensions:
>>> >> BS_K_linearized1 = 2025000000 ;
>>> >> BS_K_linearized2 = 781887360 ;
>>> >> variables:
>>> >> char BSE_RESONANT_COMPRESSED1_DONE(BS_K_linearized1) ;
>>> >> char BSE_RESONANT_COMPRESSED2_DONE(BS_K_linearized1) ;
>>> >> char BSE_RESONANT_COMPRESSED3_DONE(BS_K_linearized2) ;
>>> >> }
>>> >>
>>> >> The variable is declared as nf90_char which, according to the
>>> >> documentation should be 1 byte per element.
>>> >> Thus I would expect the total size of the file to be 1
>>> >> byte*(2*2025000000+781887360) ~ 4.5 GB
>>> >> Instead the file size is 16059445323 bytes ~ 14.96 GB, i.e. 10.46 GB
>>> >> more and a factor 3.33 bigger
>>> >>
>>> >> This happens consistently if I consider the file
>>> >> netcdf ndb {
>>> >> dimensions:
>>> >> complex = 2 ;
>>> >> BS_K_linearized1 = 2025000000 ;
>>> >> BS_K_linearized2 = 781887360 ;
>>> >> variables:
>>> >> float BSE_RESONANT_LINEARIZED1(BS_K_linearized1, complex) ;
>>> >> char BSE_RESONANT_LINEARIZED1_DONE(BS_K_linearized1) ;
>>> >> float BSE_RESONANT_LINEARIZED2(BS_K_linearized1, complex) ;
>>> >> char BSE_RESONANT_LINEARIZED2_DONE(BS_K_linearized1) ;
>>> >> float BSE_RESONANT_LINEARIZED3(BS_K_linearized2, complex) ;
>>> >> char BSE_RESONANT_LINEARIZED3_DONE(BS_K_linearized2) ;
>>> >> }
>>> >> The float component should weight ~36 GB while the char component should
>>> >> be identical to before, i.e. 4.5 GB for a total of 40.5 GB
>>> >> The file is instead ~ 50.96 GB, i.e. again a factor 10.46 GB bigger than
>>> >> expected.
>>> >>
>>> >> Why ?
>>> >>
>>> >> My character variables are something like
>>> >> "tnnnntnnnntnnnnnnnntnnnnnttnnnnnnnnnnnnnnnnt..."
>>> >> but the file size is already like that just after the file creation,
>>> >> i.e. before filling it.
>>> >>
>>> >> Few info about the library, compiled linking to HDF5 (hdf5-1.8.18), with
>>> >> parallel IO support:
>>> >> Name: netcdf
>>> >> Description: NetCDF Client Library for C
>>> >> URL: http://www.unidata.ucar.edu/netcdf
>>> >> Version: 4.4.1.1
>>> >> Libs: -L${libdir} -lnetcdf -ldl -lm
>>> >> /nfs/data/bin/Yambo/gcc-8.1.0/openmpi-3.1.0/yambo_ext_libs/gfortran/mpifort/v4/parallel/lib/libhdf5hl_fortran.a
>>> >>
>>> >> /nfs/data/bin/Yambo/gcc-8.1.0/openmpi-3.1.0/yambo_ext_libs/gfortran/mpifort/v4/parallel/lib/libhdf5_fortran.a
>>> >>
>>> >> /nfs/data/bin/Yambo/gcc-8.1.0/openmpi-3.1.0/yambo_ext_libs/gfortran/mpifort/v4/parallel/lib/libhdf5_hl.a
>>> >>
>>> >> /nfs/data/bin/Yambo/gcc-8.1.0/openmpi-3.1.0/yambo_ext_libs/gfortran/mpifort/v4/parallel/lib/libhdf5.a
>>> >> -lz -lm -ldl -lcurl
>>> >> Cflags: -I${includedir}
>>> >>
>>> >> Name: netcdf-fortran
>>> >> Description: NetCDF Client Library for Fortran
>>> >> URL: http://www.unidata.ucar.edu/netcdf
>>> >> Version: 4.4.4
>>> >> Requires.private: netcdf > 4.1.1
>>> >> Libs: -L${libdir} -lnetcdff
>>> >> Libs.private: -L${libdir} -lnetcdff -lnetcdf
>>> >> Cflags: -I${includedir}
>>> >>
>>> >> Best,
>>> >> D.
>>> >> --
>>> >> Davide Sangalli, PhD
>>> >> CNR-ISM, Division of Ultrafast Processes in Materials (FLASHit) and MaX
>>> >> Centre
>>> >> Area della Ricerca di Roma 1, 00016 Monterotondo Scalo, Italy
>>> >> http://www.ism.cnr.it/en/davide-sangalli-cv/
>>> >> http://www.max-centre.eu/
>>>
>>>
