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第39节 Update containers vendor 更新容器供应商


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Issue Description

  • https://github.com/containers/common/issues/1376

  • https://github.com/sealerio/sealer/issues/2147

  • [ ] support set load tmp dir for save and load, we could set tmp-dir flag to sysContext.BigFilesTemporaryDir.

  • [ ] Waiting for a separate functions Or string flag from containers SDK, which will not guess what type of input tar file. this is more time-saving.

more to see : containers/common#1376open in new window

Describe what feature you want

for 1 , we could use --tmp-dir flag to do it.

sealer load -i my.tar --tmp-dir /root/my-tmp
sealer save abc:v1 -o my.tar --tmp-dir /root/my-tmp
  • load: load a sealer image from a tar file: Load the sealer image from the tar file
  • save: save sealer image to a tar file : Save Save the sealer image as a tar file

related go mod version:

go get  github.com/containers/buildah@v1.29.1
go get  github.com/containers/common@v0.51.0
go get  github.com/containers/image/v5@v5.24.1
go get  github.com/containers/ocicrypt@v1.1.7
go get  github.com/containers/storage@v1.45.3

[optimize] add a new parameter to LoadOptions

I found that If i knew the format of the tar file in advance , the program wouldn't need to guess the format, which will save a lot of time.

so , should we add a new parameter to indicate the format of load package on LoadOptions ?

  • https://github.com/containers/common/blob/28ebcc64cf9af714badd8abd5521ed49545642c0/libimage/load.go#L33
// we have 4 functions, so a maximum of 4 errors
loadErrors := make([]error, 0, 4)
for _, f := range []func() ([]string, string, error){

That sounds like a nice improvement assuming the user knows exactly the format of the archive.

If this is for a new caller, I think a set of separate functions (Runtime.LoadDockerArchive etc.) would be simpler.

If this is for the primary podman load $path code path, yes, an option probably makes sense — and it would be great to update as many callers as possible to use that option; heuristically guessing among four possibly quite expensive readers is very inefficient and historically resulted in bad error messages (which we have, sort of, fixed by just listing all of the error messages…)

Set up temporary directory

the reason is that some image is very large, and require at least three times free disk to load. I see that current default temporary directory is the /var/tmp/ directory. If we could set the work temporary directory, we can separate it from the system disk which will avoid load failure.

That’s configurable in c/image via BigFilesTemporaryDir, and c/common/libimage seems to read containers.conf for that at least in some places, so that would be the setting to tweak. (I didn’t check if LoadDockerArchive applies this setting; if not, that should be added.)

Yes setting this in containers.conf, or setting the TMPDIR environment variable allow you to customize this.

计划

For sealer :

sealer save abc:v1 -o my.tar --tmp-dir /root/my-tmp

  • [x] add a flag

    	// TODO: Waiting for implementation, not yet supported
	flags.StringVar(&loadOpts.TmpDir, "tmp-dir", "", "Set temporary directory when load image. if not set, use system temporary directory(`/var/tmp/`)")

  • [ ] come true MultiImageArchive

    	// MultiImageArchive - if true, the container engine allows for storing
	// archives (e.g., of the docker-archive transport) with multiple
	// images.  By default, Podman creates single-image archives.
	MultiImageArchive bool `toml:"multi_image_archive,omitempty"`

  • [ ] update pack

  • [ ] Temporary load directory primitives, garbage collection

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