From 06dcd45ff81e06bc8cf40ed487c0b2652d346a5a Mon Sep 17 00:00:00 2001 From: John DeNisco Date: Thu, 26 Jul 2018 12:45:10 -0400 Subject: Initial commit of Sphinx docs Change-Id: I9fca8fb98502dffc2555f9de7f507b6f006e0e77 Signed-off-by: John DeNisco --- docs/usecases/vhost/vhost05.rst | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 docs/usecases/vhost/vhost05.rst (limited to 'docs/usecases/vhost/vhost05.rst') diff --git a/docs/usecases/vhost/vhost05.rst b/docs/usecases/vhost/vhost05.rst new file mode 100644 index 00000000000..4eba6e17101 --- /dev/null +++ b/docs/usecases/vhost/vhost05.rst @@ -0,0 +1,25 @@ +.. _vhost05: + +Limitations +----------- +There are some limitations when using the qemu vhost driver. Some are described in this section. + +Performance +^^^^^^^^^^^ + +VPP performance with vHost is limited by the Qemu vHost driver. FD.io VPP 18.04 CSIT vHost testing +shows with 2 threads, 2 cores and a Queue size of 1024 the maximum NDR throughput was about 7.5 Mpps. +This is about the limit at this time. + +For all the details on the CSIT VM vhost connection refer to the +`CSIT VM vHost performance tests `_. + + +Features +^^^^^^^^ + +These are the features not supported with FD.io VPP vHost. + +* VPP implements vHost in device mode only. VPP is intended to work with Qemu which implements vHost in driver mode, it does not implement vHost driver mode. +* VPP vHost implementation does not support checksum or transmit segmentation offload. +* VPP vHost implementation does not support packet receive filtering feature for controlling receive traffic. -- cgit 1.2.3-korg