latency peaks with short frames

[yoram123]

hi ,

I have a quad core x.86 board which i have checked latency performance.

The setup is :

Test equipment GBe port 1 <> 1gbe nic port 1  board --- 1gbe nic port 2  board <> Test equipment GBe port 2

At first i installed centos 6.5 directly on the board .

configured the board to be linux router and measured latency over time.

Got 100 microsec  with steady results in short frames 82Bytes/frame

Then , i have installed ESXi 5.5 on the board , and on top of it i have created vm centos 6.5 with same image.

repeated the tests and got non stable results with latency peaks between 5 milisec to 10 milisec.

when i repeat the test with long frames 1500Bytes the problem is almost gone.

How can i tune the vmware for low latency on short frames ?

BR,

Yoram

[JarryG]

Which vNIC do you use? Generally, vmxnet3 delivers better performance than e1000/e1000e, but VM has to use proper driver for it (in case of CentOS it means current kernel, as vmxnet3-driver is part of kernel-tree)...

[yoram123]

Hi ,

Its VMXNET3 indeed

BR,

Yoram