BuildKit：https://github.com/moby/buildkit Stargz Snapshotter：https://github.com/containerd/stargz-snapshotter

1. Copyright(c)2021 NTT Corp. All Rights Reserved
BuildKit Lazy Pull
2021/1/19

2. Copyright(c)2021 NTT Corp. All Rights Reserved
GitHub:@ktock / Twitter:@TokunagaKohei
Container Runtime Meetup
1/28 2
https://runtime.connpass.com/event/198071/

3. Copyright(c)2021 NTT Corp. All Rights Reserved
FROM ubuntu:20.04
RUN apt-get update &&
apt-get install –y figlet
COPY ./hello.sh /hello.sh
Dockerfile
RUN
COPY
pull
l
• 3
l
•

4. Copyright(c)2021 NTT Corp. All Rights Reserved
l
l 4 Base image
COPY –-from=A
COPY –-from=B
A B

5. Copyright(c)2021 NTT Corp. All Rights Reserved
( )( pull )
5
pulling packages accounts for 76% of container start time,
but only 6.4% of that data is read [Harter et al. 2016]
[Harter et al. 2016] Tyler Harter, Brandon Salmon, Rose Liu, Andrea C. Arpaci-Dusseau, Remzi H. Arpaci-Dusseau. "Slacker: Fast Distribution with
Lazy Docker Containers". 14th USENIX Conference on File and Storage Technologies (FAST ’16). February 22–25, 2016, Santa Clara, CA, USA

6. Copyright(c)2021 NTT Corp. All Rights Reserved
pull
temporary
l CI temporary 6
6 pull
l 6 6 pull

7. Copyright(c)2021 NTT Corp. All Rights Reserved
BuildKit
l
l --mount
l LLB7
l
l Kubernetes
l
docker build
l Docker 18.09 Docker
l Linux Docker DOCKER_BUILDKIT=1 Docker Buildx7
l Docker Desktop 2.4
https://github.com/moby/buildkit

8. Copyright(c)2021 NTT Corp. All Rights Reserved
BuildKit Lazy Pull ”pull ”
FROM ghcr.io/stargz-containers/golang:1.15.3-esgz as dev
COPY ./hello.go /hello.go
RUN go build -o hello /hello.go
lazy
pull
• /usr/local/go/bin/go
• /usr/local/go/src/fmt/…
etc...
Pull COPY RUN
golang:1.15.3-esgz pull
eStargz
l BuildKit v0.8.0 eStargz lazy pulling experimental
l pull
• eStargz BuildKit lazy pull
• → FROM pull COPY RUN pull
l 8
https://medium.com/nttlabs/buildkit-lazypull-66c37690963f

9. Copyright(c)2021 NTT Corp. All Rights Reserved
Stargz Snapshotter lazy pulling
l BuildKit containerd 9 Stargz Snapshotter https://github.com/containerd/stargz-
snapshotter
l eStargz pull
• rootfs FUSE
Stargz
Snapshotter
rootfs FUSE
Lazy
pull
eStargz
pull
BuildKit
Stargz Snapshotter containerd Kubernetes lazy pulling
https://medium.com/nttlabs/startup-containers-in-lightning-speed-with-lazy-image-distribution-on-containerd-243d94522361

10. Copyright(c)2021 NTT Corp. All Rights Reserved
eStargz
tar.gz
HTTP Range Request 1
/ pull
bin/ls
etc/group
usr/bin/apt
/ gzip
tar.gz
1
eStargz
bin/ls
usr/bin/apt
entrypoint.sh
bin/bash Range Request
0
bin/bash
entrypoint.sh
TOCEntries footer
l gzip OCI
• → lazy pull 1
l 1
• Google CRFS https://github.com/google/crfs 0 stargz
• 0
l 0
Ø NW

11. Copyright(c)2021 NTT Corp. All Rights Reserved
eStargz
l Docker 1 eStargz
l Kaniko nerdctl ko 1 eStargz
l eStargz
snapshotter prefetch
•
1
•
proc eStargz

12. Copyright(c)2021 NTT Corp. All Rights Reserved
Hello World
l Hello World 12
• 3
• gcc:10.2.0
• golang:1.15.3-buster
• python:3.9.0-buster
• Dockerfile: https://github.com/ktock/stargz-snapshotter/tree/bbbmeasure/script/buildkit/measure/sample
• 3
l GitHub Actions Ubuntu runner (eastus2)
l GitHub Container Registry
FROM ghcr.io/stargz-containers/golang:1.15.3-buster-esgz AS dev
COPY ./main.go /go/src/
RUN cd /go/src && go build -o hello ./main.go
FROM ghcr.io/stargz-containers/alpine:3.10.2-esgz
COPY --from=dev /go/src/hello /hello
ENTRYPOINT [ "/hello" ]
Dockerfile golang:1.15.3

13. Copyright(c)2021 NTT Corp. All Rights Reserved
Hello World ( export )
golang-1.15.3-bustergcc-10.2.0 python-3.9.0-buster
eStargz 3
eStargz 3
1

14. Copyright(c)2021 NTT Corp. All Rights Reserved
Buildx Lazy Pull BuildKit
DEMO
https://medium.com/nttlabs/buildkit-lazypull-66c37690963f

15. Copyright(c)2021 NTT Corp. All Rights Reserved
l lazy pulling
• https://github.com/moby/buildkit/pull/1733
l export lazy 1
• pull
• Cross-repo mount 5
push lazy
5
l rootless
experimental

16. Copyright(c)2021 NTT Corp. All Rights Reserved
Hello World ( export )
6 export pull
alpine:3.10.2 5.67MB 6 export 6
NW 6
6 python:3.9.0-slim 117MB
golang-1.15.3-bustergcc-10.2.0 python-3.9.0-buster
pull 6
push6 pull
1
6
export pull 1
OCI tar 1
export --output type=oci

17. Copyright(c)2021 NTT Corp. All Rights Reserved
( )Cross-repo mount pull/push ( )
BuildKit
Lazy pull
Cross-repo mount
push
l 1 cross-repo mount
pull/push
• 1push
push 1mount push 1
• lazy1 7
pull
push

18. Copyright(c)2021 NTT Corp. All Rights Reserved
l cross-repo mount rootless
l
• Bugfix 8
l
•
l etc…
Lazy pulling Stargz Snapshotter
l eStargz OCI on-going OCI
• https://github.com/opencontainers/image-spec/issues/815
l eStargz 1
• Kaniko Google GGCR_EXPERIMENT_ESTARGZ=1
• https://github.com/GoogleContainerTools/kaniko
• nerdctl containerd Docker CLI by NTT
• https://github.com/AkihiroSuda/nerdctl
eStargz Stargz Snapshotter

19. Copyright(c)2021 NTT Corp. All Rights Reserved
l 9
• Pull
• Temporary fresh1 pull
l BuildKit v0.8.0 9eStargz lazy pulling
• CI 1 1
1
• eStargz lazy pulling 1 +
• containerd Stargz Snapshotter lazy pulling
• containerd Kubernetes lazy pulling
l
• Stargz Snapshotter eStargz
Feedbacks and suggestions are always welcome!
https://github.com/containerd/stargz-snapshotter