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diff --git a/c_src/raid/memory.h b/c_src/raid/memory.h
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+/*
+ * Copyright (C) 2013 Andrea Mazzoleni
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __RAID_MEMORY_H
+#define __RAID_MEMORY_H
+
+/**
+ * Memory alignment provided by raid_malloc().
+ *
+ * It should guarantee good cache performance everywhere.
+ */
+#define RAID_MALLOC_ALIGN 256
+
+/**
+ * Memory displacement to avoid cache address sharing on contiguous blocks,
+ * used by raid_malloc_vector().
+ *
+ * When allocating a sequence of blocks with a size of power of 2,
+ * there is the risk that the addresses of each block are mapped into the
+ * same cache line and prefetching predictor, resulting in a lot of cache
+ * sharing if you access all the blocks in parallel, from the start to the
+ * end.
+ *
+ * To avoid this effect, it's better if all the blocks are allocated
+ * with a fixed displacement trying to reduce the cache addresses sharing.
+ *
+ * The selected displacement was chosen empirically with some speed tests
+ * with 8/12/16/20/24 data buffers of 256 KB.
+ *
+ * These are the results in MB/s with no displacement:
+ *
+ *            sse2
+ *    gen1   15368 [MB/s]
+ *    gen2    6814 [MB/s]
+ *    genz    3033 [MB/s]
+ *
+ * These are the results with displacement resulting in improvments
+ * in the order of 20% or more:
+ *
+ *            sse2
+ *    gen1   21936 [MB/s]
+ *    gen2   11902 [MB/s]
+ *    genz    5838 [MB/s]
+ *
+ */
+#define RAID_MALLOC_DISPLACEMENT (7*256)
+
+/**
+ * Aligned malloc.
+ * Use an alignment suitable for the raid functions.
+ */
+void *raid_malloc(size_t size, void **freeptr);
+
+/**
+ * Arbitrary aligned malloc.
+ */
+void *raid_malloc_align(size_t size, size_t align_size, void **freeptr);
+
+/**
+ * Aligned vector allocation.
+ * Use an alignment suitable for the raid functions.
+ * Returns a vector of @n pointers, each one pointing to a block of
+ * the specified @size.
+ * The first @nd elements are reversed in order.
+ */
+void **raid_malloc_vector(int nd, int n, size_t size, void **freeptr);
+
+/**
+ * Arbitrary aligned vector allocation.
+ */
+void **raid_malloc_vector_align(int nd, int n, size_t size, size_t align_size, size_t displacement_size, void **freeptr);
+
+/**
+ * Fills the memory vector with pseudo-random data based on the specified seed.
+ */
+void raid_mrand_vector(unsigned seed, int n, size_t size, void **vv);
+
+/**
+ * Tests the memory vector for RAM problems.
+ * If a problem is found, it crashes.
+ */
+int raid_mtest_vector(int n, size_t size, void **vv);
+
+#endif
+