Dear community,
I would like to ask often but still didn’t solved question, why apps/services is running much much slover inside docker, then directly running on host system.
I spend a lot of time to solve this situation but without success. I tested it on multiple systems with multiple processors and multiple architectures together with multiple images inside docker, but situation was always same: Processes and apps running inside docker is running slower (not signifficantly, but multiple times slower!). For example, building same nodejs app with same conditions is running multiple times slower inside docker than outside docker (caching is not the reason, I’m sure).
Building on host system takes 3 minutes, build same app takes inside docker takes about 20 minutes Tested with multiple host machines, with multiple docker images, result was the same.
Probably, you will be asking me for docker info, but I think, this is not relevant (some issue in configuration), because as I written, I tested it on multiple machines, with multiple architectures and etc. and situation was the same.
By the another questions in this forum, I’m not alone with this experience.
Therefore my question is, if this slowdown is feature and normal behavior of Docker or if it is something wrong. I cannot trust, that this slowdown is OK, I was expected, that docker performance will be similar than on host machine.
Also I don’t know, if this slowdown is comming from CPU performance, memory operations or disk operations. If zou can recommend me some simple tools to measure it, please share with me to deeper investigate the reason.
Thanks a lot for an each help.