Commit 418af5b3 authored by Ilya Dryomov's avatar Ilya Dryomov
Browse files

libceph: lower exponential backoff delay 



The current setting allows the backoff to climb up to 5 minutes.  This
is too high -- it becomes hard to tell whether the client is stuck on
something or just in backoff.

In userspace, ms_max_backoff is defaulted to 15 seconds.  Let's do the
same.

Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent b77f8f0e

include/linux/ceph/messenger.h

+2 −2
Original line number Diff line number Diff line
@@ -241,8 +241,8 @@ struct ceph_msg { 
};



/* ceph connection fault delay defaults, for exponential backoff */

#define BASE_DELAY_INTERVAL	(HZ/2)

#define MAX_DELAY_INTERVAL	(5 * 60 * HZ)

#define BASE_DELAY_INTERVAL	(HZ / 4)

#define MAX_DELAY_INTERVAL	(15 * HZ)



/*

 * A single connection with another host.

net/ceph/messenger.c

+9 −3
Original line number Diff line number Diff line
@@ -2812,6 +2812,9 @@ static int queue_con_delay(struct ceph_connection *con, unsigned long delay) 
		return -ENOENT;

	}



	if (delay >= HZ)

		delay = round_jiffies_relative(delay);



	dout("%s %p %lu\n", __func__, con, delay);

	if (!queue_delayed_work(ceph_msgr_wq, &con->work, delay)) {

		dout("%s %p - already queued\n", __func__, con);
@@ -2871,7 +2874,7 @@ static bool con_backoff(struct ceph_connection *con) 
	if (!con_flag_test_and_clear(con, CON_FLAG_BACKOFF))

		return false;



	ret = queue_con_delay(con, round_jiffies_relative(con->delay));

	ret = queue_con_delay(con, con->delay);

	if (ret) {

		dout("%s: con %p FAILED to back off %lu\n", __func__,

			con, con->delay);
@@ -3018,10 +3021,13 @@ static void con_fault(struct ceph_connection *con) 
	} else {

		/* retry after a delay. */

		con->state = CON_STATE_PREOPEN;

		if (con->delay == 0)

		if (!con->delay) {

			con->delay = BASE_DELAY_INTERVAL;

		else if (con->delay < MAX_DELAY_INTERVAL)

		} else if (con->delay < MAX_DELAY_INTERVAL) {

			con->delay *= 2;

			if (con->delay > MAX_DELAY_INTERVAL)

				con->delay = MAX_DELAY_INTERVAL;

		}

		con_flag_set(con, CON_FLAG_BACKOFF);

		queue_con(con);

	}