How much slower will MySQL be in Docker (Linux)?

Question

linux

How much slower is MySQL through Docker than native Linux?

After all, if docker uses the same file system and the same kernel, then, in theory, it should be fast, but is there some kind of layer?

How slow is she?

Answer 1

This layer is called Cgroups and, in theory, it should not interfere at all, since programs running natively also work through this layer, only with different policies. There is one exception - network interfaces, they usually also work natively, but sometimes they are brought into a virtual bridge (switch), there is an overhead for additional viewing of packet headers and tags. But usually you can simply ignore all this and say that the speed of programs in docker/lxc/cgroups is practically no different from the speed of native applications.
Another exception is if we use hardware-controlled virtualization (KVM), here, depending on the configuration, we can lose from 1.5 to 10%.