From: jbeulich@suse.com
Subject: netback: bump tx queue length
Patch-mainline: n/a
References: bnc#849404

Various values are being discussed in
https://bugzilla.redhat.com/show_bug.cgi?id=539626, with no clear
explanation of why they in the end picked 1024. Be a little more
conservative for the time being.

--- head.orig/drivers/xen/netback/interface.c	2013-10-29 10:24:04.000000000 +0100
+++ head/drivers/xen/netback/interface.c	2013-11-26 11:42:30.000000000 +0100
@@ -51,7 +51,7 @@
  * run a timer (tx_queue_timeout) to drain the queue when the interface is
  * blocked.
  */
-static unsigned long netbk_queue_length = 32;
+static unsigned long netbk_queue_length = 512;
 module_param_named(queue_length, netbk_queue_length, ulong, 0644);
 
 static void __netif_up(netif_t *netif)
