1. Git in the Large – Tips & Tricks
Mark Waite

2. Git in the Large – Tips & Tricks
Mark Waite – mark.earl.waite@gmail.com

3. Remote
• Central
repo
Master
• Pipeline
cache repo
• Polling repo
Agent
• Pipeline
cache repo
• Local repo
• Workspace
Git in the Large - Concepts
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4. • Reduce remote work and network transfer with:
• Reference repository
• Narrow refspec
• Shallow clone
• Large file support
Git in the Large – Help the Remote
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• Remote repository
• Includes all history
• Sends requested history
• Includes all large files
• Sends requested large files

5. Reference Repository
• New repositories can “reference” an existing repository
rather than downloading the referenced data
• Positive
– Reduce network data transfer
– Reduce local repository storage
• Negative
– Reference copies not automatically updated
– Destroying reference repository damages all references
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6. Narrow Refspec
• Refspec defines history retrieval start points (breadth)
• Positive
– If you only need one branch, narrow refspec retrieves one
– Reduce local repository storage
• Negative
– Copies history only for matching branches
– Refspec patterns severely limited
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7. Shallow Clone
• Shallow clone defines history retrieval depth
• Positive
– If you only need most recent commit, use shallow clone
– Reduce local repository storage
• Negative
– Breaks merge workflows
– Change reports can be incomplete
– Command line git only (no JGit)
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8. Large File Support
• Git extension that stores large files outside repository
• Positive
– High performance
– Very active development
– Reduces local repository storage
• Negative
– Requires LFS extension
– Requires extra support from hosting provider
– No ssh support (http / https only)
– No submodule support in the git plugin (yet)
– Large file history requires separate request (LFS commands)
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9. Git in the Large – Help the Master
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• Master
• Scans repositories
• Detects changes
• Computes changes
• Reduce master work and disc use with:
• Reference repository
• Large file support

10. Git in the Large – Help the Agent
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• Agent
• Fills workspace
• Builds the job
• Reduce agent work and disc space with:
• Narrow refspec
• Shallow clone
• Reference repository
• Large file support
• Sparse checkout

11. Sparse Checkout
• Sparse checkout defines directories for checkout
(workspace breadth)
• Positive
– If you only need a subtree, sparse checkout creates it
– Reduces local working directory storage
• Negative
– Subtree checkout is not the full tree
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