Dockerfile Revisited

hello@bill.dev (Bill) — Fri, 26 Jul 2024 16:08:00 +0100

For years I’ve been building container images by using the COPY command to bring files from my Docker context into the build container.

FROM golang:1.22 AS build

WORKDIR /src/build
COPY . .

RUN go mod verify
RUN CGO_ENABLED=0 GOOS=linux GOARCH=arm64 go build -o /app .

FROM scratch
COPY --from=build /app .
CMD ["./app"]

Today I came across the following section in the Docker documentation.

“You’ll mostly want to use COPY for copying files from one stage to another in a multi-stage build. If you need to add files from the build context to the container temporarily to execute a RUN instruction, you can often substitute the COPY instruction with a bind mount instead.”

Use the Kubernetes downwards API to set GOMEMLIMIT

hello@bill.dev (Bill) — Wed, 14 Sep 2022 21:10:06 +0100

Go 1.19 introduced the ability to tune the way the garbage collector works by setting a soft memory limit. One recommendation is to use this new memory limit when deploying in a container environment. This post looks at using the Kubernetes Downward API to set this soft limit.

Do I need a Soft Memory Limit

Do take advantage of the memory limit when the execution environment of your Go program is entirely within your control, and the Go program is the only program with access to some set of resources (i.e. some kind of memory reservation, like a container memory limit).

A good example is the deployment of a web service into containers with a fixed amount of available memory.

Container on Bill Glover

Dockerfile Revisited

Use the Kubernetes downwards API to set GOMEMLIMIT

Do I need a Soft Memory Limit