--- block/deadline-iosched.c

+++ block/deadline-iosched.c

@@ -17,10 +17,10 @@

/*

* See Documentation/block/deadline-iosched.txt

*/

-static const int read_expire = HZ / 4; /* max time before a read is submitted. */

+static const int read_expire = HZ / 2; /* max time before a read is submitted. */

static const int write_expire = 5 * HZ; /* ditto for writes, these limits are SOFT! */

-static const int writes_starved = 4; /* max times reads can starve a write */

-static const int fifo_batch = 1; /* # of sequential requests treated as one

+static const int writes_starved = 2; /* max times reads can starve a write */

+static const int fifo_batch = 16; /* # of sequential requests treated as one

by the above parameters. For throughput. */

struct deadline_data {

@@ -77,8 +77,10 @@ static void

deadline_add_rq_rb(struct deadline_data *dd, struct request *rq)

{

struct rb_root *root = deadline_rb_root(dd, rq);

+ struct request *__alias;

- elv_rb_add(root, rq);

+ while (unlikely(__alias = elv_rb_add(root, rq)))

+ deadline_move_request(dd, __alias);

}

static inline void

@@ -352,7 +354,7 @@ static void *deadline_init_queue(struct

dd->fifo_expire[READ] = read_expire;

dd->fifo_expire[WRITE] = write_expire;

dd->writes_starved = writes_starved;

- dd->front_merges = 0;

+ dd->front_merges = 1;

dd->fifo_batch = fifo_batch;

return dd;

}