always chunk data

for small datasets:
- only one chunk
- no compression

python/damask/_result.py

@@ -1355,15 +1355,17 @@ class Result:
                         dataset[...] = result['data']
                         dataset.attrs['overwritten'] = True
                     else:
-                        if result['data'].size >= chunk_size*2:
                         shape = result['data'].shape
+                        if result['data'].size >= chunk_size*2:
                             chunks = (chunk_size//np.prod(shape[1:]),)+shape[1:]
+                            compression = ('gzip',6)
+                        else:
+                            chunks = shape
+                            compression = (None,None)
                         dataset = f[group].create_dataset(result['label'],data=result['data'],
                                                           maxshape=shape, chunks=chunks,
-                                                              compression='gzip', compression_opts=6,
+                                                          compression=compression[0], compression_opts=compression[1],
                                                           shuffle=True,fletcher32=True)
-                        else:
-                            dataset = f[group].create_dataset(result['label'],data=result['data'])
 
                     now = datetime.datetime.now().astimezone()
                     dataset.attrs['created'] = now.strftime('%Y-%m-%d %H:%M:%S%z') if h5py3 else \

src/HDF5_utilities.f90

@@ -77,10 +77,12 @@ module HDF5_utilities
   end interface HDF5_addAttribute
 
 #ifdef PETSC
-  logical, parameter, private :: parallel_default = .true.
+  logical, parameter :: parallel_default = .true.
 #else
-  logical, parameter, private :: parallel_default = .false.
+  logical, parameter :: parallel_default = .false.
 #endif
+  logical :: compression_possible
+
   public :: &
     HDF5_utilities_init, &
     HDF5_read, &
@@ -103,13 +105,13 @@ contains
 !--------------------------------------------------------------------------------------------------
 subroutine HDF5_utilities_init
 
-  integer         :: hdferr
+  integer :: hdferr, HDF5_major, HDF5_minor, HDF5_release, deflate_info
   integer(SIZE_T) :: typeSize
 
+
   print'(/,a)', ' <<<+-  HDF5_Utilities init  -+>>>'
 
-!--------------------------------------------------------------------------------------------------
-!initialize HDF5 library and check if integer and float type size match
+
   call h5open_f(hdferr)
   if (hdferr < 0) error stop 'HDF5 error'
 
@@ -123,6 +125,13 @@ subroutine HDF5_utilities_init
   if (int(storage_size(0.0_pReal),SIZE_T)/=typeSize*8) &
     error stop 'pReal does not match H5T_NATIVE_DOUBLE'
 
+  call H5get_libversion_f(HDF5_major,HDF5_minor,HDF5_release,hdferr)
+  if (hdferr < 0) error stop 'HDF5 error'
+  call H5Zget_filter_info_f(H5Z_FILTER_DEFLATE_F,deflate_info,hdferr)
+  if (hdferr < 0) error stop 'HDF5 error'
+  compression_possible = (HDF5_major == 1 .and. HDF5_minor >= 12) .and. &                           ! https://forum.hdfgroup.org/t/6186
+                         ior(H5Z_FILTER_ENCODE_ENABLED_F,deflate_info) > 0
+
 end subroutine HDF5_utilities_init
 
 
@@ -1909,9 +1918,10 @@ subroutine initialize_write(dset_id, filespace_id, memspace_id, plist_id, &
 
   integer, dimension(worldsize) :: writeSize                                                        !< contribution of all processes
   integer(HID_T) ::  dcpl
-  integer :: ierr, hdferr, HDF5_major, HDF5_minor, HDF5_release
+  integer :: ierr, hdferr
   integer(HSIZE_T), parameter :: chunkSize = 1024_HSIZE_T**2/8_HSIZE_T
 
+
 !-------------------------------------------------------------------------------------------------
 ! creating a property list for transfer properties (is collective when writing in parallel)
   call h5pcreate_f(H5P_DATASET_XFER_F, plist_id, hdferr)
@@ -1938,23 +1948,23 @@ subroutine initialize_write(dset_id, filespace_id, memspace_id, plist_id, &
   totalShape = [myShape(1:ubound(myShape,1)-1),int(sum(writeSize),HSIZE_T)]
 
 !--------------------------------------------------------------------------------------------------
-! compress (and chunk) larger datasets
+! chunk dataset, enable compression for larger datasets
   call h5pcreate_f(H5P_DATASET_CREATE_F, dcpl, hdferr)
   if (hdferr < 0) error stop 'HDF5 error'
-  if(product(totalShape) >= chunkSize*2_HSIZE_T) then
-    call H5get_libversion_f(HDF5_major,HDF5_minor,HDF5_release,hdferr)
-    if (hdferr < 0) error stop 'HDF5 error'
-    if (HDF5_major == 1 .and. HDF5_minor >= 12) then                                                ! https://forum.hdfgroup.org/t/6186
-      call h5pset_chunk_f(dcpl, size(totalShape), getChunks(totalShape,chunkSize), hdferr)
-      if (hdferr < 0) error stop 'HDF5 error'
+
   call h5pset_shuffle_f(dcpl, hdferr)
   if (hdferr < 0) error stop 'HDF5 error'
-      call h5pset_deflate_f(dcpl, 6, hdferr)
-      if (hdferr < 0) error stop 'HDF5 error'
   call h5pset_Fletcher32_f(dcpl,hdferr)
   if (hdferr < 0) error stop 'HDF5 error'
+
+  if (product(totalShape) >= chunkSize*2_HSIZE_T) then
+    call h5pset_chunk_f(dcpl, size(totalShape), getChunks(totalShape,chunkSize), hdferr)
+    if (hdferr < 0) error stop 'HDF5 error'
+    if (compression_possible) call h5pset_deflate_f(dcpl, 6, hdferr)
+  else
+    call h5pset_chunk_f(dcpl, size(totalShape), totalShape, hdferr)
   endif
-  endif
+  if (hdferr < 0) error stop 'HDF5 error'
 
 !--------------------------------------------------------------------------------------------------
 ! create dataspace in memory (local shape) and in file (global shape)