From: Torben Mathiasen After a lot of testing and measuring we decided to increase the read-ahead for the CISS driver in 2.6 to 1MB. --- 25-akpm/drivers/block/cciss.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletion(-) diff -puN drivers/block/cciss.c~cciss-increase-vm-readahead drivers/block/cciss.c --- 25/drivers/block/cciss.c~cciss-increase-vm-readahead Wed Feb 4 13:57:02 2004 +++ 25-akpm/drivers/block/cciss.c Wed Feb 4 13:57:02 2004 @@ -103,7 +103,7 @@ static struct board_type products[] = { /*define how many times we will try a command because of bus resets */ #define MAX_CMD_RETRIES 3 -#define READ_AHEAD 128 +#define READ_AHEAD 256 #define NR_CMDS 384 /* #commands that can be outstanding */ #define MAX_CTLR 8 @@ -2501,6 +2501,7 @@ static int __devinit cciss_init_one(stru if (!q) goto clean4; + q->backing_dev_info.ra_pages = READ_AHEAD; hba[i]->queue = q; q->queuedata = hba[i]; _