Merge pull request #2504 from MikeMcC399/alpine-description

docs: update Alpine size and musl description

Author: MikeMcC399

README.md

@@ -182,37 +182,32 @@ Active Long Term Support version of Node.js. See also [Long Term Support](#long-
 
 ### `node:alpine`
 
-This image is based on the popular
-[Alpine Linux project](https://alpinelinux.org), available in
-[the `alpine` official image](https://hub.docker.com/_/alpine). Alpine Linux is
-much smaller than most distribution base images (~5MB), and thus leads to much
-slimmer images in general.
-
-This variant is highly recommended when final image size being as small as
-possible is desired. The main caveat to note is that it does use
-[musl libc](https://musl.libc.org/) instead of
-[glibc and friends](https://www.etalabs.net/compare_libcs.html), so certain
-software might run into issues depending on the depth of their libc
-requirements. However, most software doesn't have an issue with this, so this
-variant is usually a very safe choice. See
-[this Hacker News comment thread](https://news.ycombinator.com/item?id=10782897)
-for more discussion of the issues that might arise and some pro/con comparisons
-of using Alpine-based images.
-
-One common issue that may arise is a missing shared library required for use of
-`process.dlopen`. To add the missing shared libraries to your image:
-
-- Starting from Alpine v3.19, you can use the
-[`gcompat`](https://pkgs.alpinelinux.org/package/v3.19/main/x86/gcompat) package
-to add the missing shared libraries: `apk add --no-cache gcompat`
-
-To minimize image size, it's uncommon for additional related tools
-(such as `git` or `bash`) to be included in Alpine-based images. Using this
-image as a base, add the things you need in your own Dockerfile
-(see the [`alpine` image description](https://hub.docker.com/_/alpine/) for
-examples of how to install packages if you are unfamiliar).
-
-To make the image size even smaller, you can [bundle without npm/yarn](./docs/BestPractices.md#smaller-images-without-npmyarn).
+This image is based on
+[Alpine Linux](https://alpinelinux.org). Because base
+[alpine](https://hub.docker.com/_/alpine) images are smaller
+than corresponding base
+[debian](https://hub.docker.com/_/debian) images, the resulting
+`node:alpine` Docker images are around 25% smaller than the
+Debian-based `node:slim` images.
+
+Alpine images use the C library
+[musl libc](https://musl.libc.org/), not the GNU C library
+[glibc](https://sourceware.org/glibc/) used by Debian.
+
+Generally, applications written for Debian (`glibc`) will not run under Alpine (`musl`).
+Some compatibility issues may be resolvable by installing the Alpine
+[`gcompat`](https://pkgs.alpinelinux.org/package/v3.23/main/x86/gcompat)
+GNU C Library compatibility layer for musl package.
+Use `apk add --no-cache gcompat` to install.
+
+Tools such as `git` or `bash` are not included in `node:alpine*` based images. The
+[Alpine documentation](https://docs.alpinelinux.org/) describes how to find and
+install additional packages using `apk` (Alpine Package Keeper).
+
+The
+[Best Practices document](./docs/BestPractices.md), in the section
+[Smaller images without npm/yarn](./docs/BestPractices.md#smaller-images-without-npmyarn),
+shows how to produce a custom image by removing package managers in a multi-stage build.
 
 ### `node:bullseye`