In setups involving a DRBD-proxy and connections that experience a lot of
buffer-bloat it might be necessary to set ping-timeout to an
unusual high value. By default DRBD uses the same value to wait if a newly
established TCP-connection is stable. Since the DRBD-proxy is usually located
in the same data center such a long wait time may hinder DRBD's connect process.
In such setups socket-check-timeout should be set to
at least to the round trip time between DRBD and DRBD-proxy. I.e. in most
cases to 1.
Signed-off-by: Philipp Reisner <philipp.reis...@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenb...@linbit.com>
---
drivers/block/drbd/drbd_receiver.c | 46 +++++++++++++++++++++++++-------------
include/linux/drbd_genl.h | 1 +
include/linux/drbd_limits.h | 5 +++++
3 files changed, 36 insertions(+), 16 deletions(-)
diff --git a/drivers/block/drbd/drbd_receiver.c
b/drivers/block/drbd/drbd_receiver.c
index 7da83f3..b89e6fb 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -819,7 +819,7 @@ static int receive_first_packet(struct drbd_connection
*connection, struct socke
* drbd_socket_okay() - Free the socket if its connection is not okay
* @sock: pointer to the pointer to the socket.
*/
-static int drbd_socket_okay(struct socket **sock)
+static bool drbd_socket_okay(struct socket **sock)
{
int rr;
char tb[4];
@@ -837,6 +837,30 @@ static int drbd_socket_okay(struct socket **sock)
return false;
}
}
+
+static bool connection_established(struct drbd_connection *connection,
+ struct socket **sock1,
+ struct socket **sock2)
+{
+ struct net_conf *nc;
+ int timeout;
+ bool ok;
+
+ if (!*sock1 || !*sock2)
+ return false;
+
+ rcu_read_lock();
+ nc = rcu_dereference(connection->net_conf);
+ timeout = (nc->sock_check_timeo ?: nc->ping_timeo) * HZ / 10;
+ rcu_read_unlock();
+ schedule_timeout_interruptible(timeout);
+
+ ok = drbd_socket_okay(sock1);
+ ok = drbd_socket_okay(sock2) && ok;
+
+ return ok;
+}
+
/* Gets called if a connection is established, or if a new minor gets created
in a connection */
int drbd_connected(struct drbd_peer_device *peer_device)
@@ -878,8 +902,8 @@ static int conn_connect(struct drbd_connection *connection)
struct drbd_socket sock, msock;
struct drbd_peer_device *peer_device;
struct net_conf *nc;
- int vnr, timeout, h, ok;
- bool discard_my_data;
+ int vnr, timeout, h;
+ bool discard_my_data, ok;
enum drbd_state_rv rv;
struct accept_wait_data ad = {
.connection = connection,
@@ -923,17 +947,8 @@ static int conn_connect(struct drbd_connection *connection)
}
}
- if (sock.socket && msock.socket) {
- rcu_read_lock();
- nc = rcu_dereference(connection->net_conf);
- timeout = nc->ping_timeo * HZ / 10;
- rcu_read_unlock();
- schedule_timeout_interruptible(timeout);
- ok = drbd_socket_okay(&sock.socket);
- ok = drbd_socket_okay(&msock.socket) && ok;
- if (ok)
- break;
- }
+ if (connection_established(connection, &sock.socket,
&msock.socket))
+ break;
retry:
s = drbd_wait_for_connect(connection, &ad);
@@ -979,8 +994,7 @@ randomize:
goto out_release_sockets;
}
- ok = drbd_socket_okay(&sock.socket);
- ok = drbd_socket_okay(&msock.socket) && ok;
+ ok = connection_established(connection, &sock.socket,
&msock.socket);
} while (!ok);
if (ad.s_listen)
diff --git a/include/linux/drbd_genl.h b/include/linux/drbd_genl.h
index 71fc924..7b131ed 100644
--- a/include/linux/drbd_genl.h
+++ b/include/linux/drbd_genl.h
@@ -174,6 +174,7 @@ GENL_struct(DRBD_NLA_NET_CONF, 5, net_conf,
/* 9: __str_field_def(31, DRBD_GENLA_F_MANDATORY, name,
SHARED_SECRET_MAX) */
/* 9: __u32_field(32, DRBD_F_REQUIRED | DRBD_F_INVARIANT,
peer_node_id) */
__flg_field_def(33, 0 /* OPTIONAL */, csums_after_crash_only,
DRBD_CSUMS_AFTER_CRASH_ONLY_DEF)
+ __u32_field_def(34, 0 /* OPTIONAL */, sock_check_timeo,
DRBD_SOCKET_CHECK_TIMEO_DEF)
)
GENL_struct(DRBD_NLA_SET_ROLE_PARMS, 6, set_role_parms,
diff --git a/include/linux/drbd_limits.h b/include/linux/drbd_limits.h
index 9d2df1d..8ac8c5d 100644
--- a/include/linux/drbd_limits.h
+++ b/include/linux/drbd_limits.h
@@ -225,4 +225,9 @@
#define DRBD_AL_STRIPE_SIZE_MAX 16777216
#define DRBD_AL_STRIPE_SIZE_DEF 32
#define DRBD_AL_STRIPE_SIZE_SCALE 'k' /* kilobytes */
+
+#define DRBD_SOCKET_CHECK_TIMEO_MIN 0
+#define DRBD_SOCKET_CHECK_TIMEO_MAX DRBD_PING_TIMEO_MAX
+#define DRBD_SOCKET_CHECK_TIMEO_DEF 0
+#define DRBD_SOCKET_CHECK_TIMEO_SCALE '1'
#endif
--
1.9.1
--
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