http_flood in docker revisited

My last post (over 2 years ago) was my initial tests of running my http_flood project under docker. At the time, there was a huge performance impact running through docker. Performance dropped by almost 90%.

Two years later, things are a bit different.

Bare metal:

duration=3.364873568s megabytes=10000.0 speed=2971.9MB/s

Inside docker:

duration=7.283130136s megabytes=10000.0 speed=1373.0MB/s

There is still some overhead, but that is still over 10 gigabit.

What is very interesting, is that running inside docker using –net=host, gives;

inside docker with net=host:

duration=3.329915691s megabytes=10000.0 speed=3003.1MB/s

How does this manage to be faster than the bare metal process? Most likely the google/golang container I am using is running a newer version of go that peforms better.