Scaling analysys of Merge

1. Fetch revisions O(a)
2. Common Ancestor [O(b)] O(h)
3. Calculate tree merge O(c) [+ O(b) + O(d)] + O(i)

• text merge O(e * e * f) + O(b)

4. Find filesystem conflicts O(c)
5. Resolve filesystem conflicts O(g)
6. Apply changes O(c) + O(log(d))
7. Set pending merges O(1)
8. Print conflicts O(g)
9. Print changes O(c)

a:revisions missing from repo: b:nodes in the revision graph: c:files that differ between base and other: d:number of files in the tree e:number of lines in the text f:number of files requiring text merge g:number of conflicts (g <= c) h:humber of uncommon ancestors i:number of revisions between base and other

Needs

• Access to revision graph proportional to number of revisions read
• Access to changed file metadata proportional to number of changes and number of intervening revisions.
• O(1) access to fulltexts

Notes

Multiparent deltas may offer some nice properties for performance of annotation based merging.