===== fs/reiserfs/stree.c 1.19 vs edited =====
--- 1.19/fs/reiserfs/stree.c	Tue Jul 16 09:58:57 2002
+++ edited/fs/reiserfs/stree.c	Wed Jul 17 12:02:17 2002
@@ -598,26 +598,32 @@
 
 
 
-#ifdef SEARCH_BY_KEY_READA
+#define SEARCH_BY_KEY_READA 32
 
 /* The function is NOT SCHEDULE-SAFE! */
-static void search_by_key_reada (struct super_block * s, int blocknr)
+static void search_by_key_reada (struct super_block * s, 
+                                 struct buffer_head **bh, 
+				 unsigned long *b, int num)
 {
-    struct buffer_head * bh;
+    int i,j;
   
-    if (blocknr == 0)
-	return;
-
-    bh = getblk (s->s_dev, blocknr, s->s_blocksize);
-  
-    if (!buffer_uptodate (bh)) {
-	ll_rw_block (READA, 1, &bh);
+    for (i = 0 ; i < num ; i++) {
+	bh[i] = sb_getblk (s, b[i]);
+	if (buffer_uptodate(bh[i])) {
+	    brelse(bh[i]);
+	    break;
+	}
+	touch_buffer(bh[i]);
+    } 
+    if (i) {
+	ll_rw_block(READA, i, bh);
+    }
+    for(j = 0 ; j < i ; j++) {
+        if (bh[j])
+	    brelse(bh[j]);
     }
-    bh->b_count --;
 }
 
-#endif
-
 /**************************************************************************
  * Algorithm   SearchByKey                                                *
  *             look for item in the Disk S+Tree by its key                *
@@ -660,6 +666,9 @@
     int				n_node_level, n_retval;
     int 			right_neighbor_of_leaf_node;
     int				fs_gen;
+    struct buffer_head *reada_bh[SEARCH_BY_KEY_READA];
+    unsigned long      reada_blocks[SEARCH_BY_KEY_READA];
+    int reada_count = 0;
 
 #ifdef CONFIG_REISERFS_CHECK
     int n_repeat_counter = 0;
@@ -694,11 +703,11 @@
 	fs_gen = get_generation (p_s_sb);
 	expected_level --;
 
-#ifdef SEARCH_BY_KEY_READA
-	/* schedule read of right neighbor */
-	search_by_key_reada (p_s_sb, right_neighbor_of_leaf_node);
-#endif
-
+	/* schedule read of right neighbors */
+	if (reada_count) {
+	    search_by_key_reada (p_s_sb, reada_bh, reada_blocks, reada_count);
+	    reada_count = 0;
+	}
 	/* Read the next tree node, and set the last element in the path to
            have a pointer to it. */
 	if ( ! (p_s_bh = p_s_last_element->pe_buffer =
@@ -786,11 +795,19 @@
 	   position in the node. */
 	n_block_number = B_N_CHILD_NUM(p_s_bh, p_s_last_element->pe_position);
 
-#ifdef SEARCH_BY_KEY_READA
-	/* if we are going to read leaf node, then calculate its right neighbor if possible */
-	if (n_node_level == DISK_LEAF_NODE_LEVEL + 1 && p_s_last_element->pe_position < B_NR_ITEMS (p_s_bh))
-	    right_neighbor_of_leaf_node = B_N_CHILD_NUM(p_s_bh, p_s_last_element->pe_position + 1);
-#endif
+	/* if we are going to read leaf node, then try to find good leaves
+	** for read ahead as well.  Don't bother for stat data though
+	*/
+	if (n_node_level == DISK_LEAF_NODE_LEVEL + 1 && 
+	    p_s_last_element->pe_position < B_NR_ITEMS (p_s_bh) &&
+	    !is_statdata_cpu_key(p_s_key))
+	{
+	    int pos = p_s_last_element->pe_position;
+	    int limit = B_NR_ITEMS(p_s_bh);
+	    while(pos <= limit && reada_count < SEARCH_BY_KEY_READA) { 
+	        reada_blocks[reada_count++] = B_N_CHILD_NUM(p_s_bh, pos++);
+	    }
+        }
     }
 }