{"id":17,"date":"2010-02-23T16:20:51","date_gmt":"2010-02-23T21:20:51","guid":{"rendered":"http:\/\/virtualizeplanet.com\/wordpress\/?p=17"},"modified":"2010-03-19T19:14:39","modified_gmt":"2010-03-20T00:14:39","slug":"vswitch-local-speed","status":"publish","type":"post","link":"https:\/\/read.virtualizeplanet.com\/?p=17","title":{"rendered":"vSwitch Local Speed"},"content":{"rendered":"

A client told me today he thought he was having poor backup performance over a virtual network. But when he started debugging he noticed that it wasn’t just Backup that was the problem it was all network IO through a local vswitch. He started the conversation by asking me what I expect to see in network throughput between 2 VMs localised on the same vswitch. He informed me no matter what he tried in terms of using a vswitch with\/without a pNIC and trying different types of vNIC he couldn’t push 240mbits\/s. He asked him the obvious question which was “Is there anything else happening on the system that could be impacting net performance, like CPU overhead” and the answer was “no”.
\nSo I decided to test it for myself.<\/p>\n

As did my client I used the Netperf tool to test throughput between the 2 VMs. To use NetPerf you run:
\nC:\\Netserver.exe on one VM
\nand then\u00a0
\nC:\\Netclient.exe \u2013H hostname (of the first system)
\non the other VM.<\/p>\n

After a few seconds you should get a result displayed in mbits\/s
\nAnd just like my client I tested a vswitch with\/without a pNIC and different types of vNIC. I also tested different hosts to get varied result. The problem is I saw results which I’d expect to see, and on average I saw speeds of 500mbits\/s<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Flexible<\/span><\/td>\n1<\/span><\/td>\n2<\/span><\/td>\nAverage<\/span><\/td>\n<\/tr>\n
ESX1<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n<\/tr>\n
vswitch +pNIC<\/td>\n502<\/td>\n594<\/td>\n548<\/td>\n<\/tr>\n
vswitch -pNIC<\/td>\n608<\/td>\n565<\/td>\n586.5<\/td>\n<\/tr>\n
ESX2<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n<\/tr>\n
vswitch +pNIC<\/td>\n461<\/td>\n482<\/td>\n471.5<\/td>\n<\/tr>\n
vswitch -pNIC<\/td>\n261<\/td>\n495<\/td>\n378<\/td>\n<\/tr>\n
\u00a0<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n<\/tr>\n
VMXNet3<\/span><\/td>\n1<\/span><\/td>\n2<\/span><\/td>\nAverage<\/span><\/td>\n<\/tr>\n
ESX1<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n<\/tr>\n
vswitch +pNIC<\/td>\n641<\/td>\n621<\/td>\n631<\/td>\n<\/tr>\n
vswitch -pNIC<\/td>\n628<\/td>\n593<\/td>\n610.5<\/td>\n<\/tr>\n
ESX2<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n\u00a0<\/td>\n<\/tr>\n
vswitch +pNIC<\/td>\n465<\/td>\n496<\/td>\n480.5<\/td>\n<\/tr>\n
vswitch -pNIC<\/td>\n531<\/td>\n533<\/td>\n532<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"excerpt":{"rendered":"

A client told me today he thought he was having poor backup performance over a virtual network. But when he started debugging he noticed that it wasn’t just Backup that was the problem it was all network IO through a local vswitch. He started the conversation by asking me what I expect to see in […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-17","post","type-post","status-publish","format-standard","hentry","category-vmware"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t