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diff --git a/HDF5Examples/C/Perf/h5slabwrite.c b/HDF5Examples/C/Perf/h5slabwrite.c
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+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * All rights reserved.                                                      *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/* This example shows different data writing patterns to generate data files
+ * that will exhibit substantially different data read speed. The files
+ * contain 2-D chunk storage datasets.
+ * The 2 writing patterns are:
+ * 1. Random--chunks are wriitten in the random order.
+ * 2. ByRow--chunks are written by row order.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "../Perf/h5slab.h"
+#include "hdf5.h"
+
+/* Write the chunks in the row order.  This provides good and bad read
+ * performance if the read pattern is by row and by column respectively.
+ *
+ * Created by Albert Cheng and Christian Chilan 2010/7/13.
+ */
+int
+createfilebyrow(void)
+{
+    hid_t         file_id, dset_id, filespace, memspace, fapl, dxpl, dcpl;
+    hsize_t       dimsf[2], count[2], offset[2], chunk_dims[2] = {CX, CY};
+    char         *data, dataval, table[RC];
+    unsigned long i, j, l, cx;
+    fapl = H5Pcreate(H5P_FILE_ACCESS);
+    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dxpl = H5Pcreate(H5P_DATASET_XFER);
+    H5Pset_chunk(dcpl, 2, chunk_dims);
+    fapl = dxpl = H5P_DEFAULT;
+    file_id     = H5Fcreate("row_alloc.h5", H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
+    dimsf[0]    = NX;
+    dimsf[1]    = NY;
+    filespace   = H5Screate_simple(2, dimsf, NULL);
+    dset_id     = H5Dcreate(file_id, "dataset1", H5T_NATIVE_CHAR, filespace, H5P_DEFAULT, dcpl, H5P_DEFAULT);
+    count[0]    = CX;
+    count[1]    = NY;
+    memspace    = H5Screate_simple(2, count, NULL);
+
+    data = (char *)malloc(count[0] * count[1] * sizeof(char));
+
+    /* writing the whole chunked rows each time. */
+    for (l = 0; l < RC; l++) {
+
+        offset[0] = l * CX;
+        offset[1] = 0;
+
+        /* fill with values according to row number */
+        for (i = 0; i < count[0]; i++)
+            for (j = 0; j < count[1]; j++)
+                data[i * count[1] + j] = l;
+
+        H5Sselect_hyperslab(filespace, H5S_SELECT_SET, offset, NULL, count, NULL);
+        H5Dwrite(dset_id, H5T_NATIVE_CHAR, memspace, filespace, dxpl, data);
+    }
+
+    free(data);
+    H5Dclose(dset_id);
+    H5Sclose(filespace);
+    H5Sclose(memspace);
+    H5Pclose(dxpl);
+    H5Pclose(dcpl);
+    H5Pclose(fapl);
+    H5Fclose(file_id);
+    return 0;
+}
+
+/* Write the chunks in a random pattern.  This provides a read performance
+ * worse than when the chunks are written and read in the same order, whether
+ * it is by row or by column.
+ *
+ * Created by Albert Cheng and Christian Chilan 2010/7/13.
+ */
+int
+createfilerandom(void)
+{
+    hid_t         file_id, dset_id, filespace, memspace, fapl, dxpl, dcpl;
+    hsize_t       dimsf[2], count[2], offset[2], chunk_dims[2] = {CX, CY};
+    char         *data, table[RC][CC];
+    unsigned long i, j, cx, cy;
+    fapl = H5Pcreate(H5P_FILE_ACCESS);
+    dcpl = H5Pcreate(H5P_DATASET_CREATE);
+    dxpl = H5Pcreate(H5P_DATASET_XFER);
+    H5Pset_chunk(dcpl, 2, chunk_dims);
+    fapl = dxpl = H5P_DEFAULT;
+    file_id     = H5Fcreate("random_alloc.h5", H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
+    dimsf[0]    = NX;
+    dimsf[1]    = NY;
+    filespace   = H5Screate_simple(2, dimsf, NULL);
+    dset_id     = H5Dcreate(file_id, "dataset1", H5T_NATIVE_CHAR, filespace, H5P_DEFAULT, dcpl, H5P_DEFAULT);
+    count[0]    = CX;
+    count[1]    = CY;
+    memspace    = H5Screate_simple(2, count, NULL);
+    data        = (char *)malloc(count[0] * count[1] * sizeof(char));
+
+    for (i = 0; i < RC; i++)
+        for (j = 0; j < CC; j++)
+            table[i][j] = 0;
+
+    for (i = 0; i < RC * CC; i++) {
+        do {
+            cx = rand() % RC;
+            cy = rand() % CC;
+        } while (table[cx][cy]);
+
+        for (j = 0; j < count[0] * count[1]; j++) {
+            data[j] = cx + cy;
+        }
+
+        table[cx][cy] = 1;
+
+        offset[0] = cx * CX;
+        offset[1] = cy * CY;
+
+        H5Sselect_hyperslab(filespace, H5S_SELECT_SET, offset, NULL, count, NULL);
+        H5Dwrite(dset_id, H5T_NATIVE_CHAR, memspace, filespace, dxpl, data);
+    }
+
+    free(data);
+    H5Dclose(dset_id);
+    H5Sclose(filespace);
+    H5Sclose(memspace);
+    H5Pclose(dxpl);
+    H5Pclose(dcpl);
+    H5Pclose(fapl);
+    H5Fclose(file_id);
+    return 0;
+}
+
+int
+main(int argc, char **argv)
+{
+    createfilebyrow();
+    createfilerandom();
+}