[svn-r22641] Dectris project: I revised the code per Quincey's and Neil's comments. I added a performance benchmark program dectris_perf.c in the test/ directory.

Tested on koala and jam.

4 files changed, 640 insertions, 25 deletions

diff --git a/test/Makefile.am b/test/Makefile.am
index 0197e99..006e24b 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -40,7 +40,7 @@ TEST_PROG= testhdf5 lheap ohdr stab gheap cache cache_api cache_tagging \
            pool accum hyperslab istore bittests dt_arith \
            dtypes dsets cmpd_dset filter_fail extend external efc objcopy links unlink \
            big mtime fillval mount flush1 flush2 app_ref enum \
-           set_extent ttsafe dectris_tst \
+           set_extent ttsafe dectris_tst dectris_perf \
            getname vfd ntypes dangle dtransform reserved cross_read \
            freespace mf farray earray btree2 fheap file_image
 
@@ -128,7 +128,7 @@ CHECK_CLEANFILES+=accum.h5 cmpd_dset.h5 compact_dataset.h5 dataset.h5 dset_offse
     earray.h5 efc[0-5].h5 log_vfd_out.log                            \
     new_multi_file_v16-r.h5 new_multi_file_v16-s.h5                  \
     split_get_file_image_test-m.h5 split_get_file_image_test-r.h5    \
-    file_image_core_test.h5.copy dectris.h5
+    file_image_core_test.h5.copy dectris.h5 dectris_perf.h5
 
 # Sources for testhdf5 executable
 testhdf5_SOURCES=testhdf5.c tarray.c tattr.c tchecksum.c tconfig.c tfile.c \
diff --git a/test/Makefile.in b/test/Makefile.in
index ddc481e..21706d7 100644
--- a/test/Makefile.in
+++ b/test/Makefile.in
@@ -89,8 +89,8 @@ am__EXEEXT_1 = testhdf5$(EXEEXT) lheap$(EXEEXT) ohdr$(EXEEXT) \
 	unlink$(EXEEXT) big$(EXEEXT) mtime$(EXEEXT) fillval$(EXEEXT) \
 	mount$(EXEEXT) flush1$(EXEEXT) flush2$(EXEEXT) \
 	app_ref$(EXEEXT) enum$(EXEEXT) set_extent$(EXEEXT) \
-	ttsafe$(EXEEXT) dectris_tst$(EXEEXT) getname$(EXEEXT) \
-	vfd$(EXEEXT) ntypes$(EXEEXT) dangle$(EXEEXT) \
+	ttsafe$(EXEEXT) dectris_tst$(EXEEXT) dectris_perf$(EXEEXT) \
+	getname$(EXEEXT) vfd$(EXEEXT) ntypes$(EXEEXT) dangle$(EXEEXT) \
 	dtransform$(EXEEXT) reserved$(EXEEXT) cross_read$(EXEEXT) \
 	freespace$(EXEEXT) mf$(EXEEXT) farray$(EXEEXT) earray$(EXEEXT) \
 	btree2$(EXEEXT) fheap$(EXEEXT) file_image$(EXEEXT)
@@ -148,6 +148,10 @@ dangle_SOURCES = dangle.c
 dangle_OBJECTS = dangle.$(OBJEXT)
 dangle_LDADD = $(LDADD)
 dangle_DEPENDENCIES = libh5test.la $(LIBHDF5)
+dectris_perf_SOURCES = dectris_perf.c
+dectris_perf_OBJECTS = dectris_perf.$(OBJEXT)
+dectris_perf_LDADD = $(LDADD)
+dectris_perf_DEPENDENCIES = libh5test.la $(LIBHDF5)
 dectris_tst_SOURCES = dectris_tst.c
 dectris_tst_OBJECTS = dectris_tst.$(OBJEXT)
 dectris_tst_LDADD = $(LDADD)
@@ -430,23 +434,24 @@ am__v_GEN_ = $(am__v_GEN_$(AM_DEFAULT_VERBOSITY))
 am__v_GEN_0 = @echo "  GEN   " $@;
 SOURCES = $(libh5test_la_SOURCES) accum.c app_ref.c big.c bittests.c \
 	btree2.c cache.c cache_api.c cache_tagging.c cmpd_dset.c \
-	cross_read.c dangle.c dectris_tst.c dsets.c dt_arith.c \
-	dtransform.c dtypes.c earray.c efc.c enum.c err_compat.c \
-	error_test.c extend.c external.c farray.c fheap.c file_image.c \
-	fillval.c filter_fail.c flush1.c flush2.c freespace.c \
-	gen_bad_ohdr.c gen_bogus.c gen_cross.c gen_deflate.c \
-	gen_file_image.c gen_filespace.c gen_filters.c gen_new_array.c \
-	gen_new_fill.c gen_new_group.c gen_new_mtime.c gen_new_super.c \
-	gen_noencoder.c gen_nullspace.c gen_sizes_lheap.c \
-	gen_specmetaread.c gen_udlinks.c getname.c gheap.c hyperslab.c \
-	istore.c lheap.c links.c links_env.c mf.c mount.c mtime.c \
-	ntypes.c objcopy.c ohdr.c pool.c reserved.c set_extent.c \
-	space_overflow.c stab.c tcheck_version.c $(testhdf5_SOURCES) \
-	testmeta.c $(ttsafe_SOURCES) unlink.c vfd.c
+	cross_read.c dangle.c dectris_perf.c dectris_tst.c dsets.c \
+	dt_arith.c dtransform.c dtypes.c earray.c efc.c enum.c \
+	err_compat.c error_test.c extend.c external.c farray.c fheap.c \
+	file_image.c fillval.c filter_fail.c flush1.c flush2.c \
+	freespace.c gen_bad_ohdr.c gen_bogus.c gen_cross.c \
+	gen_deflate.c gen_file_image.c gen_filespace.c gen_filters.c \
+	gen_new_array.c gen_new_fill.c gen_new_group.c gen_new_mtime.c \
+	gen_new_super.c gen_noencoder.c gen_nullspace.c \
+	gen_sizes_lheap.c gen_specmetaread.c gen_udlinks.c getname.c \
+	gheap.c hyperslab.c istore.c lheap.c links.c links_env.c mf.c \
+	mount.c mtime.c ntypes.c objcopy.c ohdr.c pool.c reserved.c \
+	set_extent.c space_overflow.c stab.c tcheck_version.c \
+	$(testhdf5_SOURCES) testmeta.c $(ttsafe_SOURCES) unlink.c \
+	vfd.c
 DIST_SOURCES = $(libh5test_la_SOURCES) accum.c app_ref.c big.c \
 	bittests.c btree2.c cache.c cache_api.c cache_tagging.c \
-	cmpd_dset.c cross_read.c dangle.c dectris_tst.c dsets.c \
-	dt_arith.c dtransform.c dtypes.c earray.c efc.c enum.c \
+	cmpd_dset.c cross_read.c dangle.c dectris_perf.c dectris_tst.c \
+	dsets.c dt_arith.c dtransform.c dtypes.c earray.c efc.c enum.c \
 	err_compat.c error_test.c extend.c external.c farray.c fheap.c \
 	file_image.c fillval.c filter_fail.c flush1.c flush2.c \
 	freespace.c gen_bad_ohdr.c gen_bogus.c gen_cross.c \
@@ -776,7 +781,7 @@ CHECK_CLEANFILES = *.chkexe *.chklog *.clog accum.h5 cmpd_dset.h5 \
 	earray.h5 efc[0-5].h5 log_vfd_out.log new_multi_file_v16-r.h5 \
 	new_multi_file_v16-s.h5 split_get_file_image_test-m.h5 \
 	split_get_file_image_test-r.h5 file_image_core_test.h5.copy \
-	dectris.h5
+	dectris.h5 dectris_perf.h5
 INCLUDES = -I$(top_srcdir)/src -I$(top_builddir)/src
 
 # Test script for error_test and err_compat
@@ -795,7 +800,7 @@ TEST_PROG = testhdf5 lheap ohdr stab gheap cache cache_api cache_tagging \
            pool accum hyperslab istore bittests dt_arith \
            dtypes dsets cmpd_dset filter_fail extend external efc objcopy links unlink \
            big mtime fillval mount flush1 flush2 app_ref enum \
-           set_extent ttsafe dectris_tst \
+           set_extent ttsafe dectris_tst dectris_perf \
            getname vfd ntypes dangle dtransform reserved cross_read \
            freespace mf farray earray btree2 fheap file_image
 
@@ -958,6 +963,9 @@ cross_read$(EXEEXT): $(cross_read_OBJECTS) $(cross_read_DEPENDENCIES)
 dangle$(EXEEXT): $(dangle_OBJECTS) $(dangle_DEPENDENCIES) 
 	@rm -f dangle$(EXEEXT)
 	$(AM_V_CCLD)$(LINK) $(dangle_OBJECTS) $(dangle_LDADD) $(LIBS)
+dectris_perf$(EXEEXT): $(dectris_perf_OBJECTS) $(dectris_perf_DEPENDENCIES) 
+	@rm -f dectris_perf$(EXEEXT)
+	$(AM_V_CCLD)$(LINK) $(dectris_perf_OBJECTS) $(dectris_perf_LDADD) $(LIBS)
 dectris_tst$(EXEEXT): $(dectris_tst_OBJECTS) $(dectris_tst_DEPENDENCIES) 
 	@rm -f dectris_tst$(EXEEXT)
 	$(AM_V_CCLD)$(LINK) $(dectris_tst_OBJECTS) $(dectris_tst_LDADD) $(LIBS)
@@ -1160,6 +1168,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/cmpd_dset.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/cross_read.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dangle.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dectris_perf.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dectris_tst.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dsets.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dt_arith.Po@am__quote@
diff --git a/test/dectris_perf.c b/test/dectris_perf.c
new file mode 100644
index 0000000..e743a19
--- /dev/null
+++ b/test/dectris_perf.c
@@ -0,0 +1,535 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
+ * access to either file, you may request a copy from help@hdfgroup.org.     *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * This test is for the DECTRIS project to the H5PSIdirect_write function
+ *
+ */
+
+#include "h5test.h"
+#include <zlib.h>
+#include <math.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+ 
+const char *FILENAME[] = {
+    "dectris_perf",
+    "unix.raw",
+    NULL
+};
+
+#define DIRECT_DSET        "direct_dset"
+#define COMPRESSED_DSET       "compressed_dset"
+#define NO_COMPRESS_DSET   "no_compress_dset"
+#define RANK         3
+#define NX     100
+#define NY     100
+#define NZ     25
+#define CHUNK_NX     1 
+#define CHUNK_NY     100
+#define CHUNK_NZ     25
+
+#define DEFLATE_SIZE_ADJUST(s) (ceil(((double)(s))*1.001)+12)
+char        filename[1024];
+unsigned int *outbuf[NX];
+size_t         data_size[NX];
+double       total_size = 0.0;
+unsigned int *direct_buf[NX];
+double       MB = 1048576.0;
+
+/*--------------------------------------------------
+ * Function to report IO rate
+ *--------------------------------------------------
+ */
+void reportTime(struct timeval start, double mbytes)
+{
+    struct timeval timeval_stop,timeval_diff;
+
+    /*end timing*/
+    gettimeofday(&timeval_stop,NULL);
+
+    /* Calculate the elapsed gettimeofday time */
+    timeval_diff.tv_usec=timeval_stop.tv_usec-start.tv_usec;
+    timeval_diff.tv_sec=timeval_stop.tv_sec-start.tv_sec;
+
+    if(timeval_diff.tv_usec<0) {
+        timeval_diff.tv_usec+=1000000;
+        timeval_diff.tv_sec--;
+    } /* end if */
+
+/*printf("mbytes=%lf, sec=%lf, usec=%lf\n", mbytes, (double)timeval_diff.tv_sec, (double)timeval_diff.tv_usec);*/
+    printf("MBytes/second: %lf\n", (double)mbytes/((double)timeval_diff.tv_sec+((double)timeval_diff.tv_usec/(double)1000000.0)));        
+}
+
+/*--------------------------------------------------
+ *  Create file, datasets, and initialize data
+ *--------------------------------------------------
+ */
+int create_file(hid_t fapl_id)
+{
+    hid_t       file;                          /* handles */
+    hid_t       fapl;
+    hid_t       cparms;
+    hid_t       dataspace, dataset;
+    hsize_t     dims[RANK]  = {NX, NY, NZ};        
+    hsize_t     chunk_dims[RANK] ={CHUNK_NX, CHUNK_NY, CHUNK_NZ};
+    unsigned int         aggression = 9;     /* Compression aggression setting */
+    int         ret;
+    int         i, j, n;
+
+    unsigned int *p;
+    size_t      buf_size = CHUNK_NY*CHUNK_NZ*sizeof(unsigned int);
+
+    const Bytef *z_src;
+    Bytef	    *z_dst;		/*destination buffer		*/
+    uLongf	     z_dst_nbytes = (uLongf)DEFLATE_SIZE_ADJUST(buf_size);
+    uLong	     z_src_nbytes = (uLong)buf_size;
+
+    TESTING("Create a file and dataset");
+
+    /*
+     * Create the data space with unlimited dimensions.
+     */
+    if((dataspace = H5Screate_simple(RANK, dims, NULL)) < 0)
+        TEST_ERROR;
+
+    /*
+     * Create a new file. If file exists its contents will be overwritten.
+     */
+    if((file = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id)) < 0)
+        TEST_ERROR;
+
+    /*
+     * Modify dataset creation properties, i.e. enable chunking and compression
+     */
+    if((cparms = H5Pcreate(H5P_DATASET_CREATE)) < 0)
+        TEST_ERROR;
+
+    if(H5Pset_chunk( cparms, RANK, chunk_dims) < 0)
+        TEST_ERROR;
+
+    /*
+     * Create a new dataset within the file using cparms
+     * creation properties.
+     */
+    if((dataset = H5Dcreate2(file, NO_COMPRESS_DSET, H5T_NATIVE_INT, dataspace, H5P_DEFAULT,
+			cparms, H5P_DEFAULT)) < 0)
+        TEST_ERROR;
+
+    if(H5Dclose(dataset) < 0)
+        TEST_ERROR;
+
+    /* Set compression */
+    if(H5Pset_deflate( cparms, aggression) < 0)
+        TEST_ERROR;
+
+    if((dataset = H5Dcreate2(file, DIRECT_DSET, H5T_NATIVE_INT, dataspace, H5P_DEFAULT,
+			cparms, H5P_DEFAULT)) < 0)
+        TEST_ERROR;
+
+    if(H5Dclose(dataset) < 0)
+        TEST_ERROR;
+
+
+    if((dataset = H5Dcreate2(file, COMPRESSED_DSET, H5T_NATIVE_INT, dataspace, H5P_DEFAULT,
+			cparms, H5P_DEFAULT)) < 0)
+        TEST_ERROR;
+
+    if(H5Dclose(dataset) < 0)
+        TEST_ERROR;
+
+    if(H5Fclose(file) < 0) 
+        TEST_ERROR;
+
+    if(H5Sclose(dataspace) < 0)
+        TEST_ERROR;
+
+    if(H5Pclose(cparms) < 0)
+        TEST_ERROR;
+
+    /* Initialize data for chunks */
+    for(i = 0; i < NX; i++) {
+	p = direct_buf[i] = (unsigned int*)malloc(CHUNK_NY*CHUNK_NZ*sizeof(unsigned int));
+        
+        for(j=0; j < CHUNK_NY*CHUNK_NZ; j++, p++)
+            *p = rand() % 65000;
+
+        z_src = (const Bytef*)direct_buf[i];
+
+        z_dst_nbytes = (uLongf)DEFLATE_SIZE_ADJUST(buf_size);
+        /* Allocate output (compressed) buffer */
+        outbuf[i] = (unsigned int*)malloc((size_t)z_dst_nbytes);
+        z_dst = (Bytef *)outbuf[i];
+
+        /* Perform compression from the source to the destination buffer */
+        ret = compress2(z_dst, &z_dst_nbytes, z_src, z_src_nbytes, aggression);
+
+        data_size[i] = (size_t)z_dst_nbytes;
+        total_size += data_size[i];
+
+        /* Check for various zlib errors */
+        if(Z_BUF_ERROR == ret) {
+            fprintf(stderr, "overflow");
+            TEST_ERROR;
+        } else if(Z_MEM_ERROR == ret) {
+	    fprintf(stderr, "deflate memory error");
+            TEST_ERROR;
+        } else if(Z_OK != ret) {
+	    fprintf(stderr, "other deflate error");
+            TEST_ERROR;
+        }
+    }
+
+
+    PASSED();
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dataset);
+        H5Sclose(dataspace);
+        H5Pclose(cparms);
+        H5Fclose(file);
+    } H5E_END_TRY;
+    return 1;
+}
+
+/*--------------------------------------------------
+ *  Benchmark the performance of the new function
+ *--------------------------------------------------
+ */
+int
+test_direct_write(hid_t fapl_id)
+{
+    hid_t       file;                          /* handles */
+    hid_t       dataspace, dataset;
+    hid_t       dxpl;
+    herr_t      status;
+    int         i;
+
+    unsigned    filter_mask = 0;
+    hsize_t     offset[RANK+1] = {0, 0, 0, 0};
+
+    struct timeval timeval_start;    
+    
+    TESTING("H5PSIdirect_write for DECTRIS project");
+
+    if((dxpl = H5Pcreate(H5P_DATASET_XFER)) < 0)
+        TEST_ERROR;
+
+    /* Start the timer */
+    gettimeofday(&timeval_start,NULL);
+
+    /* Reopen the file and dataset */
+    if((file = H5Fopen(filename, H5F_ACC_RDWR|H5F_ACC_SYNC, fapl_id)) < 0)
+        TEST_ERROR;
+
+    if((dataset = H5Dopen(file, DIRECT_DSET, H5P_DEFAULT)) < 0)
+        TEST_ERROR;
+
+
+    /* Write the compressed chunk data repeatedly to cover all the chunks in the 
+     * dataset, using the direct writing function.     */ 
+    for(i=0; i<NX; i++) {
+        status = H5PSIdirect_write(dataset, dxpl, filter_mask, offset, data_size[i], outbuf[i]);
+        (offset[0])++;
+    }
+
+    /*
+     * Close/release resources.
+     */
+    H5Dclose(dataset);
+    H5Pclose(dxpl);
+    H5Fclose(file);
+  
+    /* Report the performance */ 
+    reportTime(timeval_start, (double)(total_size/MB));    
+
+    PASSED();
+    return 0;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dataset);
+        H5Pclose(dxpl);
+        H5Fclose(file);
+    } H5E_END_TRY;
+    return 1;
+}
+
+/*--------------------------------------------------
+ *  Benchmark the performance of the regular H5Dwrite
+ *  with compression filter enabled.
+ *--------------------------------------------------
+ */
+int
+test_compressed_write(hid_t fapl_id)
+{
+    hid_t       file;                          /* handles */
+    hid_t       dataspace, dataset;
+    hid_t       mem_space;
+    hsize_t     chunk_dims[RANK] ={CHUNK_NX, CHUNK_NY, CHUNK_NZ};
+    hid_t       dxpl;
+    herr_t      status;
+    int         i;
+
+    hsize_t start[RANK];  /* Start of hyperslab */
+    hsize_t stride[RANK]; /* Stride of hyperslab */
+    hsize_t count[RANK];  /* Block count */
+    hsize_t block[RANK];  /* Block sizes */
+
+    struct timeval timeval_start;    
+
+    TESTING("H5Dwrite with compression enabled");
+
+    if((dxpl = H5Pcreate(H5P_DATASET_XFER)) < 0)
+        TEST_ERROR;
+
+    if((mem_space = H5Screate_simple(RANK, chunk_dims, NULL)) < 0)
+        TEST_ERROR;
+
+    /* Start the timer */
+    gettimeofday(&timeval_start,NULL);
+
+    /* Reopen the file and dataset */
+    if((file = H5Fopen(filename, H5F_ACC_RDWR|H5F_ACC_SYNC, fapl_id)) < 0)
+        TEST_ERROR;
+
+    if((dataset = H5Dopen(file, COMPRESSED_DSET, H5P_DEFAULT)) < 0)
+        TEST_ERROR;
+
+    if((dataspace = H5Dget_space(dataset)) < 0)
+        TEST_ERROR;
+
+    start[0]  = start[1]  = start[2] = 0;
+    stride[0] = stride[1] = stride[2] = 1;
+    count[0]  = count[1]  = count[2] = 1;
+    block[0]  = CHUNK_NX; block[1]  = CHUNK_NY; block[2] = CHUNK_NZ;
+    
+    for(i=0; i<NX; i++) {
+        /*
+         * Select hyperslab for one chunk in the file
+         */
+        if((status = H5Sselect_hyperslab(dataspace, H5S_SELECT_SET, start, stride, count, block)) < 0)
+            TEST_ERROR;
+        (start[0])++;        
+
+        if((status = H5Dwrite(dataset, H5T_NATIVE_INT, mem_space, dataspace,
+    		      H5P_DEFAULT, direct_buf[i])) < 0)
+            TEST_ERROR;
+    }
+
+    /*
+     * Close/release resources.
+     */
+    H5Dclose(dataset);
+    H5Sclose(dataspace);
+    H5Sclose(mem_space);
+    H5Pclose(dxpl);
+    H5Fclose(file);
+ 
+    /* Report the performance */ 
+    reportTime(timeval_start, (double)(NX*NY*NZ*sizeof(unsigned int)/MB));    
+   
+    PASSED();
+    return 0;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dataset);
+        H5Sclose(dataspace);
+        H5Sclose(mem_space);
+        H5Pclose(dxpl);
+        H5Fclose(file);
+    } H5E_END_TRY;
+    return 1;
+}
+
+/*--------------------------------------------------
+ *  Benchmark the performance of the regular H5Dwrite
+ *  with compression
+ *--------------------------------------------------
+ */
+int
+test_no_compress_write(hid_t fapl_id)
+{
+    hid_t       file;                          /* handles */
+    hid_t       dataspace, dataset;
+    hid_t       mem_space;
+    hsize_t     chunk_dims[RANK] ={CHUNK_NX, CHUNK_NY, CHUNK_NZ};
+    hid_t       dxpl;
+    herr_t      status;
+    int         i;
+
+    hsize_t start[RANK];  /* Start of hyperslab */
+    hsize_t stride[RANK]; /* Stride of hyperslab */
+    hsize_t count[RANK];  /* Block count */
+    hsize_t block[RANK];  /* Block sizes */
+
+    struct timeval timeval_start;    
+
+    TESTING("H5Dwrite without compression");
+
+    if((dxpl = H5Pcreate(H5P_DATASET_XFER)) < 0)
+        TEST_ERROR;
+
+    if((mem_space = H5Screate_simple(RANK, chunk_dims, NULL)) < 0)
+        TEST_ERROR;
+
+    /* Start the timer */
+    gettimeofday(&timeval_start,NULL);
+
+    /* Reopen the file and dataset */
+    if((file = H5Fopen(filename, H5F_ACC_RDWR|H5F_ACC_SYNC, fapl_id)) < 0)
+        TEST_ERROR;
+
+    if((dataset = H5Dopen(file, NO_COMPRESS_DSET, H5P_DEFAULT)) < 0)
+        TEST_ERROR;
+
+    if((dataspace = H5Dget_space(dataset)) < 0)
+        TEST_ERROR;
+
+    start[0]  = start[1]  = start[2] = 0;
+    stride[0] = stride[1] = stride[2] = 1;
+    count[0]  = count[1]  = count[2] = 1;
+    block[0]  = CHUNK_NX; block[1]  = CHUNK_NY; block[2] = CHUNK_NZ;
+    
+    for(i=0; i<NX; i++) {
+        /*
+         * Select hyperslab for one chunk in the file
+         */
+        if((status = H5Sselect_hyperslab(dataspace, H5S_SELECT_SET, start, stride, count, block)) < 0)
+            TEST_ERROR;
+        (start[0])++;        
+
+        if((status = H5Dwrite(dataset, H5T_NATIVE_INT, mem_space, dataspace,
+    		      H5P_DEFAULT, direct_buf[i])) < 0)
+            TEST_ERROR;
+    }
+
+    /*
+     * Close/release resources.
+     */
+    H5Dclose(dataset);
+    H5Sclose(dataspace);
+    H5Sclose(mem_space);
+    H5Pclose(dxpl);
+    H5Fclose(file);
+ 
+    /* Report the performance */ 
+    reportTime(timeval_start, (double)(NX*NY*NZ*sizeof(unsigned int)/MB));    
+   
+    PASSED();
+    return 0;
+
+error:
+    H5E_BEGIN_TRY {
+        H5Dclose(dataset);
+        H5Sclose(dataspace);
+        H5Sclose(mem_space);
+        H5Pclose(dxpl);
+        H5Fclose(file);
+    } H5E_END_TRY;
+    return 1;
+}
+
+/*--------------------------------------------------
+ *  Benchmark the performance for writing compressed
+ *  data to a Unix file
+ *--------------------------------------------------
+ */
+int 
+test_unix_write(void)
+{
+    int file, flag;
+    ssize_t op_size;    
+    int i;
+    struct timeval timeval_start;    
+
+    TESTING("Write compressed data to a Unix file");
+
+    /* create file*/
+    flag = O_CREAT|O_TRUNC|O_WRONLY|O_SYNC;
+
+    /* Start the timer */
+    gettimeofday(&timeval_start,NULL);
+
+    if ((file=open(FILENAME[1],flag,S_IRWXU))== -1)
+        TEST_ERROR;
+
+    /* Write the compressed chunk data repeatedly to cover all the chunks in the 
+     * dataset, using the direct writing function.     */ 
+    for(i=0; i<NX; i++) {
+        op_size = write(file, outbuf[i],data_size[i]);
+        if (op_size < 0)
+        {
+            printf(" Error in writing data to file because %s \n", strerror(errno));
+            TEST_ERROR;
+        }
+        else if (op_size == 0)
+        {
+            printf(" unable to write sufficent data to file because %s \n", strerror(errno));
+            TEST_ERROR;
+        }
+    }
+
+    if (close(file) < 0)
+    {
+        printf(" unable to close the file\n");
+        TEST_ERROR;
+    }
+
+    /* Report the performance */ 
+    reportTime(timeval_start, (double)(total_size/MB));    
+
+    PASSED();
+    return 0;
+
+error:
+    return 1; 
+}
+
+/*--------------------------------------------------
+ *  Main function
+ *--------------------------------------------------
+ */
+int
+main (void)
+{
+    hid_t       fapl;
+    int         i;
+
+    /* Testing setup */
+    h5_reset();
+    fapl = h5_fileaccess();
+
+    h5_fixname(FILENAME[0], fapl, filename, sizeof filename);
+
+    create_file(fapl);
+    test_direct_write(fapl);
+    test_no_compress_write(fapl);
+    test_compressed_write(fapl);
+    test_unix_write();
+
+    for(i=0; i<NX; i++) {
+        free(outbuf[i]);
+        free(direct_buf[i]);
+    }
+ 
+    h5_cleanup(FILENAME, fapl);
+    return 0;
+}
diff --git a/test/dectris_tst.c b/test/dectris_tst.c
index f2cc356..a6bbaab 100644
--- a/test/dectris_tst.c
+++ b/test/dectris_tst.c
@@ -55,6 +55,7 @@ main (void)
     int         check[NX][NY];
     int         i, j, n;
 
+    unsigned    filter_mask = 0;
     int         direct_buf[CHUNK_NX][CHUNK_NY];
     int         check_chunk[CHUNK_NX][CHUNK_NY];
     hsize_t     offset[3] = {0, 0, 0};
@@ -159,13 +160,15 @@ main (void)
      * dataset, using the direct writing function.     */ 
     for(i=0; i<NX/CHUNK_NX; i++) {
         for(j=0; j<NY/CHUNK_NY; j++) {
-            status = H5PSIdirect_write(dataset, dxpl, offset, z_dst_nbytes, outbuf);
+            status = H5PSIdirect_write(dataset, dxpl, filter_mask, offset, z_dst_nbytes, outbuf);
             offset[1] += CHUNK_NY;
         }
         offset[0] += CHUNK_NX;
         offset[1] = 0;
     }
 
+    free(outbuf);
+
     if(H5Dclose(dataset) < 0)
         TEST_ERROR;
 
@@ -197,13 +200,83 @@ main (void)
     for(i = 0; i < CHUNK_NX; i++) {
         for(j = 0; j < CHUNK_NY; j++) {
             if(direct_buf[i][j] != check_chunk[i][j]) {
-                printf("    Read different values than written.");
+                printf("    1. Read different values than written.");
                 printf("    At index %d,%d\n", i, j);
                 printf("    direct_buf=%d, check_chunk=%d\n", direct_buf[i][j], check_chunk[i][j]); 
+                goto error;
             }
         }
     }
 
+    /* Reinitialize different data for one chunk */
+    for(i = 0; i < CHUNK_NX; i++)
+        for(j = 0; j < CHUNK_NY; j++)
+	    direct_buf[i][j] = i + j;
+
+    /* Allocate output (compressed) buffer */
+    outbuf = malloc(z_dst_nbytes);
+    z_dst = (Bytef *)outbuf;
+
+    /* Perform compression from the source to the destination buffer */
+    ret = compress2(z_dst, &z_dst_nbytes, z_src, z_src_nbytes, aggression);
+
+    /* Check for various zlib errors */
+    if(Z_BUF_ERROR == ret) {
+        fprintf(stderr, "overflow");
+        TEST_ERROR;
+    } else if(Z_MEM_ERROR == ret) {
+	fprintf(stderr, "deflate memory error");
+        TEST_ERROR;
+    } else if(Z_OK != ret) {
+	fprintf(stderr, "other deflate error");
+        TEST_ERROR;
+    }
+
+    /* Rewrite the compressed chunk data repeatedly to cover all the chunks in the 
+     * dataset, using the direct writing function.     */ 
+    offset[0] = offset[1] = 0;
+    for(i=0; i<NX/CHUNK_NX; i++) {
+        for(j=0; j<NY/CHUNK_NY; j++) {
+            status = H5PSIdirect_write(dataset, dxpl, filter_mask, offset, z_dst_nbytes, outbuf);
+            offset[1] += CHUNK_NY;
+        }
+        offset[0] += CHUNK_NX;
+        offset[1] = 0;
+    }
+
+    free(outbuf);
+
+    if(H5Dclose(dataset) < 0)
+        TEST_ERROR;
+
+    if(H5Fclose(file) < 0) 
+        TEST_ERROR;
+
+    /* Reopen the file and dataset */
+    if((file = H5Fopen(filename, H5F_ACC_RDWR, H5P_DEFAULT)) < 0)
+        TEST_ERROR;
+
+    if((dataset = H5Dopen(file, DATASETNAME, H5P_DEFAULT)) < 0)
+        TEST_ERROR;
+
+    /* Read the chunk back */
+    if((status = H5Dread(dataset, H5T_NATIVE_INT, mem_space, dataspace, H5P_DEFAULT, check_chunk)) < 0)
+        TEST_ERROR;
+
+    /* Check that the values read are the same as the values written */
+    for(i = 0; i < CHUNK_NX; i++) {
+        for(j = 0; j < CHUNK_NY; j++) {
+            if(direct_buf[i][j] != check_chunk[i][j]) {
+                printf("    2. Read different values than written.");
+                printf("    At index %d,%d\n", i, j);
+                printf("    direct_buf=%d, check_chunk=%d\n", direct_buf[i][j], check_chunk[i][j]); 
+                goto error;
+            }
+        }
+    }
+
+
+
     /*
      * Close/release resources.
      */
@@ -214,8 +287,6 @@ main (void)
     H5Pclose(dxpl);
     H5Fclose(file);
     
-    free(outbuf);
-
     h5_cleanup(FILENAME, fapl);
     PASSED();
     return 0;