Commit 098eadce authored Jun 17, 2019 by Jason Wang Committed by David S. Miller Jun 17, 2019

vhost_net: disable zerocopy by default

Vhost_net was known to suffer from HOL[1] issues which is not easy to
fix. Several downstream disable the feature by default. What's more,
the datapath was split and datacopy path got the support of batching
and XDP support recently which makes it faster than zerocopy part for
small packets transmission.

It looks to me that disable zerocopy by default is more
appropriate. It cold be enabled by default again in the future if we
fix the above issues.

[1] https://patchwork.kernel.org/patch/3787671/



Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent c681edae

drivers/vhost/net.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -36,7 +36,7 @@

		#include "vhost.h"

		static int experimental_zcopytx = 1;
		static int experimental_zcopytx = 0;
		module_param(experimental_zcopytx, int, 0444);
		MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;"
		" 1 -Enable; 0 - Disable");

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