红帽全球峰会7.5. 将容器镜像优化为较小的版本
您可以使用 bootc-base-imagectl rechunk 子命令优化输入容器镜像到具有相同文件系统树的新镜像中，但被分成可寻址的可重复生成的层，以及预先计算的 SELinux 标签。
这可提高网络效率（用于推送和拉取），因为不更改镜像构建的层可以在不造成传输的情况下被重复使用。
rechunk 操作适用于由创建新镜像 FROM <rhel-bootc> 的默认模式生成的镜像，但与仅输出单个大 tar 层的 scratch 构建结合使用特别有用。如果没有重试对输入的每个更改，如内核更新，将导致新层包括 bootc 镜像的整个内容。然后，此新层必须推送、由 registry 存储并由客户端拉取。
bootc-base-imagectl 作为 bootc 镜像的一部分提供，旨在在容器内运行，但需要将主机 containers-storage 映射到要执行的容器。
先决条件
- 您有一个之前构建的基础镜像。
流程
运行以下命令来重新扩展您的基础镜像。
sudo podman run --rm --privileged -v /var/lib/containers:/var/lib/containers \ registry.redhat.io/rhel10/rhel-bootc:latest \ /usr/libexec/bootc-base-imagectl rechunk \ quay.io/exampleos/rhel-bootc:single \ quay.io/exampleos/rhel-bootc:chunked$ sudo podman run --rm --privileged -v /var/lib/containers:/var/lib/containers \ registry.redhat.io/rhel10/rhel-bootc:latest \ /usr/libexec/bootc-base-imagectl rechunk \ quay.io/exampleos/rhel-bootc:single \ quay.io/exampleos/rhel-bootc:chunkedCopy to Clipboard Copied! Toggle word wrap Toggle overflow
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