From 668700b40a7c8727bbd2b3fd4fd22e0ce3f1aeb6 Mon Sep 17 00:00:00 2001 From: Philipp Reisner Date: Mon, 16 Mar 2015 16:08:29 +0100 Subject: drbd: Create a dedicated workqueue for sending acks on the control connection The intention is to reduce CPU utilization. Recent measurements unveiled that the current performance bottleneck is CPU utilization on the receiving node. The asender thread became CPU limited. One of the main points is to eliminate the idr_for_each_entry() loop from the sending acks code path. One exception in that is sending back ping_acks. These stay in the ack-receiver thread. Otherwise the logic becomes too complicated for no added value. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_main.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) (limited to 'drivers/block/drbd/drbd_main.c') diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 445f2c8bfa1b..938bca2df027 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -1794,15 +1794,6 @@ int drbd_send(struct drbd_connection *connection, struct socket *sock, drbd_update_congested(connection); } do { - /* STRANGE - * tcp_sendmsg does _not_ use its size parameter at all ? - * - * -EAGAIN on timeout, -EINTR on signal. - */ -/* THINK - * do we need to block DRBD_SIG if sock == &meta.socket ?? - * otherwise wake_asender() might interrupt some send_*Ack ! - */ rv = kernel_sendmsg(sock, &msg, &iov, 1, size); if (rv == -EAGAIN) { if (we_should_drop_the_connection(connection, sock)) @@ -2821,6 +2812,7 @@ enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsig goto out_idr_remove_from_resource; } kref_get(&connection->kref); + INIT_WORK(&peer_device->send_acks_work, drbd_send_acks_wf); } if (init_submitter(device)) { -- cgit v1.2.3