revlog: add a fast method for getting a list of chunks
This moves _chunkraw into the loop. Doing that improves revlog decompression --
in particular, manifest decompression -- significantly. For a 20 MB manifest
which is the result of a > 40k delta chain, hg perfmanifest improves from 0.55
seconds to 0.49 seconds.
perfmanifest: allow and require passing in a rev
Previously perfmanifest would only test tip.
perfmanifest: fix cache invalidation
The manifest cache is now stored in _mancache. The revlog cache is still stored
in _cache.
bundle: fix performance regression when bundling file changes (
issue4031)
Somewhere before 2.7, a change [
ec896f9e8894] was committed that
entailed a large performance regression when bundling (and therefore
remote cloning) repositories. For each file in the repository, it would
recompute the set of needed changesets even though it is the same for
all files. This computation would dominate bundle runtimes according to
profiler output (by 10x or more).