When multiple images share the same context, it's way faster to create a base image that contains a copy of the whole context and have the downstream builds copy from this base image instead of from the "." context.
Slow build (takes minutes):
BASE="." docker buildx bake -f slow.hcl --loadFaster build (19s):
BASE="target:base" docker buildx bake -f slow.hcl --loadThe faster solution requires changing all of our Dockerfiles.
COPY x y becomes COPY --from=base x y
It would be much simpler if we could redefine the "." context and set it to "target:base".
Another issue is visible with this example:
Even though the build takes 18.5s, almost all the build steps show 0.0s and the total sum of those steps is 4.7s. Where are he other 14s spent? When I look at the build, I have the feeling that the time taken to write the image is more than 0.7s. By the way, each time I run this build, the result is the same but it seems that the image still gets loaded over and over again.
[+] Building 18.5s (173/173) FINISHED
=> [base internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 59B 0.0s
=> [base internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg26 internal] load build context 0.0s
=> => transferring context: 7.50kB 0.0s
=> CACHED [pkg26 1/1] COPY . . 0.1s
=> [pkg26] exporting to image 0.7s
=> => exporting layers 0.0s
=> => writing image sha256:b028daff45f597ec1bf4a6a090391c5dce0fff854def9057b4ee005ee79ff8ea 0.0s
=> => writing image sha256:82f0fd8aa9e650107ba5a6909752e26afe17d183af92d54ec28396ad44af70e5 0.0s
=> [pkg04 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 360B 0.0s
=> [pkg12 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg32 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg30 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg25 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg05 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg18 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg14 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg15 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg02 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg10 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg38 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg36 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg19 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg23 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg39 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg03 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg28 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg08 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg37 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg21 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg35 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg20 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg06 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg00 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg13 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg33 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg27 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg29 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg24 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg09 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg22 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg16 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg01 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg07 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg11 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg31 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg34 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg17 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg26 internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 32B 0.0s
=> [pkg04 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg12 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg32 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg30 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg25 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg05 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg18 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg14 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg15 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg02 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg10 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg38 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg36 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg19 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg23 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg39 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg03 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg28 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg08 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg37 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg21 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg35 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg20 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg06 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg00 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg13 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg33 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg27 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg29 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg24 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg09 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg22 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg16 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg01 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg07 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg11 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg31 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg34 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg17 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg26 internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> [pkg26] resolve image config for docker.io/docker/dockerfile@sha256:9ba7531bd80fb0a858632727cf7a112fbfd19b17e94 0.0s
=> CACHED [pkg26] docker-image://docker.io/docker/dockerfile@sha256:9ba7531bd80fb0a858632727cf7a112fbfd19b17e94c4e 0.0s
=> [pkg04 internal] load .dockerignore 0.0s
=> [pkg04 internal] load build definition from Dockerfile 0.0s
=> [pkg26 internal] load metadata for docker.io/library/golang:1.19.2-alpine3.16@sha256:e4dcdac3ed37d8c2b3b8bcef29 0.0s
=> [pkg26 build 1/4] FROM docker.io/library/golang:1.19.2-alpine3.16@sha256:e4dcdac3ed37d8c2b3b8bcef2909573b2ad9c2 0.0s
=> CACHED [pkg26 build 2/4] WORKDIR /src 0.0s
=> CACHED [pkg26 build 3/4] COPY --from=base . ./ 0.9s
=> CACHED [pkg26 build 4/4] RUN go build -o main ./pkg1/ 3.0s
=> [pkg12 internal] load build definition from Dockerfile 0.0s
=> [pkg12 internal] load .dockerignore 0.0s
=> [pkg32 internal] load build definition from Dockerfile 0.0s
=> [pkg32 internal] load .dockerignore 0.0s
=> [pkg30 internal] load build definition from Dockerfile 0.0s
=> [pkg30 internal] load .dockerignore 0.0s
=> [pkg25 internal] load .dockerignore 0.0s
=> [pkg25 internal] load build definition from Dockerfile 0.0s
=> [pkg05 internal] load build definition from Dockerfile 0.0s
=> [pkg05 internal] load .dockerignore 0.0s
=> [pkg18 internal] load .dockerignore 0.0s
=> [pkg18 internal] load build definition from Dockerfile 0.0s
=> [pkg14 internal] load build definition from Dockerfile 0.0s
=> [pkg14 internal] load .dockerignore 0.0s
=> [pkg15 internal] load build definition from Dockerfile 0.0s
=> [pkg15 internal] load .dockerignore 0.0s
=> [pkg02 internal] load build definition from Dockerfile 0.0s
=> [pkg02 internal] load .dockerignore 0.0s
=> [pkg10 internal] load .dockerignore 0.0s
=> [pkg10 internal] load build definition from Dockerfile 0.0s
=> [pkg38 internal] load build definition from Dockerfile 0.0s
=> [pkg38 internal] load .dockerignore 0.0s
=> [pkg36 internal] load .dockerignore 0.0s
=> [pkg36 internal] load build definition from Dockerfile 0.0s
=> [pkg19 internal] load .dockerignore 0.0s
=> [pkg19 internal] load build definition from Dockerfile 0.0s
=> [pkg23 internal] load build definition from Dockerfile 0.0s
=> [pkg23 internal] load .dockerignore 0.0s
=> [pkg39 internal] load .dockerignore 0.0s
=> [pkg39 internal] load build definition from Dockerfile 0.0s
=> [pkg03 internal] load .dockerignore 0.0s
=> [pkg03 internal] load build definition from Dockerfile 0.0s
=> [pkg28 internal] load build definition from Dockerfile 0.0s
=> [pkg28 internal] load .dockerignore 0.0s
=> [pkg08 internal] load build definition from Dockerfile 0.0s
=> [pkg08 internal] load .dockerignore 0.0s
=> [pkg37 internal] load .dockerignore 0.0s
=> [pkg37 internal] load build definition from Dockerfile 0.0s
=> [pkg21 internal] load build definition from Dockerfile 0.0s
=> [pkg21 internal] load .dockerignore 0.0s
=> [pkg35 internal] load build definition from Dockerfile 0.0s
=> [pkg35 internal] load .dockerignore 0.0s
=> [pkg20 internal] load build definition from Dockerfile 0.0s
=> [pkg20 internal] load .dockerignore 0.0s
=> [pkg06 internal] load build definition from Dockerfile 0.0s
=> [pkg06 internal] load .dockerignore 0.0s
=> [pkg00 internal] load build definition from Dockerfile 0.0s
=> [pkg00 internal] load .dockerignore 0.0s
=> [pkg13 internal] load build definition from Dockerfile 0.0s
=> [pkg13 internal] load .dockerignore 0.0s
=> CACHED [pkg26 stage-1 1/1] COPY --from=build /src/main /main 0.0s
=> [pkg33 internal] load .dockerignore 0.0s
=> [pkg33 internal] load build definition from Dockerfile 0.0s
=> [pkg29 internal] load build definition from Dockerfile 0.0s
=> [pkg29 internal] load .dockerignore 0.0s
=> [pkg27 internal] load build definition from Dockerfile 0.0s
=> [pkg27 internal] load .dockerignore 0.0s
=> [pkg24 internal] load .dockerignore 0.0s
=> [pkg24 internal] load build definition from Dockerfile 0.0s
=> [pkg09 internal] load .dockerignore 0.0s
=> [pkg09 internal] load build definition from Dockerfile 0.0s
=> [pkg22 internal] load .dockerignore 0.0s
=> [pkg22 internal] load build definition from Dockerfile 0.0s
=> [pkg16 internal] load .dockerignore 0.0s
=> [pkg16 internal] load build definition from Dockerfile 0.0s
=> [pkg01 internal] load .dockerignore 0.0s
=> [pkg01 internal] load build definition from Dockerfile 0.0s
=> [pkg07 internal] load .dockerignore 0.0s
=> [pkg07 internal] load build definition from Dockerfile 0.0s
=> [pkg11 internal] load build definition from Dockerfile 0.0s
=> [pkg11 internal] load .dockerignore 0.0s
=> [pkg31 internal] load .dockerignore 0.0s
=> [pkg31 internal] load build definition from Dockerfile 0.0s
=> [pkg34 internal] load build definition from Dockerfile 0.0s
=> [pkg34 internal] load .dockerignore 0.0s
=> [pkg17 internal] load build definition from Dockerfile 0.0s
=> [pkg17 internal] load .dockerignore 0.0s
=> [pkg26 internal] load .dockerignore 0.0s
=> [pkg26 internal] load build definition from Dockerfile 0.0s