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2485.4.2
by Robert Collins
Add gc analysis |
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Garbage Collection |
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2506.1.1
by Alexander Belchenko
sanitize developers docs |
2 |
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2485.4.2
by Robert Collins
Add gc analysis |
3 |
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4 |
Garbage collection is used to remove data from a repository that is no longer referenced. |
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Generally this involves locking the repository and scanning all its branches |
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then generating a new repository with less data. |
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Least work we can hope to perform |
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2506.1.1
by Alexander Belchenko
sanitize developers docs |
10 |
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2485.4.2
by Robert Collins
Add gc analysis |
11 |
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* Read all branches to get initial references - tips + tags. |
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* Read through the revision graph to find unreferenced revisions. A cheap HEADS |
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list might help here by allowing comparison of the initial references to the |
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HEADS - any unreferenced head is garbage. |
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* Walk out via inventory deltas to get the full set of texts and signatures to preserve. |
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* Copy to a new repository |
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* Bait and switch back to the original |
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* Remove the old repository. |
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A possibility to reduce this would be to have a set of grouped 'known garbage |
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free' data - 'ancient history' which can be preserved in total should its HEADS |
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be fully referenced - and where the HEADS list is deliberate cheap (e.g. at the |
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top of some index). |
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2485.4.4
by Robert Collins
Add annotate roadmap. |
25 |
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possibly - null data in place without saving size. |