Added signature for changeset
ca387377df7a
Added tag 2.8.2 for changeset
ca387377df7a
i18n-ja: synchronized with
d4be314b2071
fileset, revset: do not use global parser object for thread safety
parse() cannot be called at the same time because a parser object keeps its
states. This is no problem for command-line hg client, but it would cause
strange errors in multi-threaded hgweb.
Creating parser object is not too expensive.
original:
% python -m timeit -s 'from mercurial import revset' 'revset.parse("0::tip")'
100000 loops, best of 3: 11.3 usec per loop
thread-safe:
% python -m timeit -s 'from mercurial import revset' 'revset.parse("0::tip")'
100000 loops, best of 3: 13.1 usec per loop
obsolete: order of magnitude speedup in _computebumpedset
Reminder: a changeset is said "bumped" if it tries to obsolete a immutable
changeset.
The previous algorithm for computing bumped changeset was:
1) Get all public changesets
2) Find all they successors
3) Search for stuff that are eligible for being "bumped"
(mutable and non obsolete)
The entry size of this algorithm is `O(len(public))` which is mostly the same as
`O(len(repo))`. Even this this approach mean fewer obsolescence marker are
traveled, this is not very scalable.
The new algorithm is:
1) For each potential bumped changesets (non obsolete mutable)
2) iterate over precursors
3) if a precursors is public. changeset is bumped
We travel more obsolescence marker, but the entry size is much smaller since
the amount of potential bumped should remains mostly stable with time `O(1)`.
On some confidential gigantic repo this move bumped computation from 15.19s to
0.46s (×33 speedup…). On "smaller" repo (mercurial, cubicweb's review) no
significant gain were seen. The additional traversal of obsolescence marker is
probably probably counter balance the advantage of it.
Other optimisation could be done in the future (eg: sharing precursors cache
for divergence detection)
obsolete: add an allprecursors method mirroring allsuccessors one.
Detection of bumped changeset should use `allprecursors(<mutable>)` instead or
`allsuccessors(<immutable>)` so we need the all precursors function to exists.