Support json mode build context transfer - #84
Open
JaewonHur wants to merge 5 commits into
Open
Conversation
7 tasks
JaewonHur
force-pushed
the
context-mode-json
branch
from
June 17, 2026 06:50
b4e8f4f to
e1f47c5
Compare
Tar mode transfer imposes high burden on host side as the host side proxy needs to always archive and send the entire build context. Json mode transfer avoids this, but feeds the file contents to VM on-demand when buildkitd requests. This gets lower host side computing overhead, but has more gRPC calls.
Dockerignore contains staging directory path itself to ignore that directory. ReceiveJson needs to honor it.
JaewonHur
force-pushed
the
context-mode-json
branch
from
July 31, 2026 20:26
5412fcc to
f7744f3
Compare
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
This resolves apple/container#1515.
Tar mode build context transfer imposes high burden on host side as the host side proxy always have to archive and hash entire build context directory. While it lowers the excessive gRPC when there are lots of file read requests from buildkitd, it also comes with computing overhead when build context is large. Since we support docker ignore now, buildkitd can selectively ask the non-ignored files only.
Thus, json transfer mode supports on-demand file request, avoiding archiving entire build context at start.