perf: add a perfignore command The command is meant to benchmark operations related to hgignore. Right now the command is benchmarking the loading time of the hgignore rules.

py3: use pycompat.xrange instead of xrange xrange does not exists on Python 3. Differential Revision: https://phab.mercurial-scm.org/D5302

store: write fncache only once if there are both adds and removes Differential Revision: https://phab.mercurial-scm.org/D5307

perf: disable revlogs clearing in `perftags` by default This aligns things with what `perfbookmarks` does. I decided to disable the revlogs clearing by default to focus on the core logic by default, ignoring side effects. If we prefer to emphasize the side effect, we can instead keep this on in `perftags` and enable it by default in `perfbookmarks`.

perf: add a `clear-revlogs` flag to `perfbookmarks` This flag (off by default) makes it possible to enable the refresh of the changelog and revlog. This is useful to check for costly side effects of bookmark loading. Usually, these side effects are shared with other logics (eg: tags). example output in my mercurial repo (with 1 bookmark, so not a great example): $ hg perfbookmarks ! wall 0.000044 $ hg perfbookmarks --clear-revlogs ! wall 0.001380

tags: cache `repo.changelog` access when checking tags nodes The tags reading process checks if the nodes referenced in tags exist. Caching the access to `repo.changelog` provides a large speedup for repositories with many tags. running `hg perftags` in a large private repository before: ! wall 0.393464 comb 0.390000 user 0.330000 sys 0.060000 (median of 25) after: ! wall 0.267711 comb 0.270000 user 0.210000 sys 0.060000 (median of 38)

perf: add a `clear-revlogs` flag to `perftags` This flag (on by default) makes it possible to disable the refresh of the changelog and revlog. This is useful to check for the time spent in the core tags logic without the associated side effects. Usually, these side effects are shared with other logics (eg: bookmarks). Example output in my Mercurial repository $ hg perftags ! wall 0.017919 comb 0.020000 user 0.020000 sys 0.000000 (best of 141) $ hg perftags --no-clear-revlogs ! wall 0.012982 comb 0.010000 user 0.010000 sys 0.000000 (best of 207)

perf: stop creating new revlog by hand in perftags It's better to let the repository logic create its own object. We now just clear the cache. New object will be automatically created from there.

revlog: update the documentation for `trim_endidx` The function role drifted since the function was commented.

revlog: properly detect corrupted revlog in `index_get_length` Pointed out by Yuya Nishihara.

perf: rename `perfhelper-tracecopies` to `perfhelper-pathcopies` The command it supports is called `perfpathcopies`. It seems better to align the names.

perf: add a docstring to `perfpathcopies` This will help people to find this command.

revlog: update the docstring of `ancestors` to match reality Code using this method expect the revision to be (reverse) sorted. As pointed by Yuya Nishihara, the docstring should reflect that.

remotefilelog: fix typo in docstring Differential Revision: https://phab.mercurial-scm.org/D5306

store: append to fncache if there are only new files to write Before this patch, if we have to add a new entry to fncache, we write the whole fncache again which slows things down on large fncache which have millions of entries. Addition of a new entry is common operation while pulling new files or commiting a new file. This patch adds a new fncache.addls set which keeps track of the additions happening and store them. When we write the fncache, we will just read the addls set and append those entries at the end of fncache. We make sure that the entries are new entries by loading the fncache and making sure entry does not exists there. In future if we can check if an entry is new without loading the fncache, that will speed up things more. Performance numbers for commiting a new file: mercurial repo before: 0.08784651756286621 after: 0.08474504947662354 mozilla-central before: 1.83314049243927 after: 1.7054164409637451 netbeans before: 0.7953150272369385 after: 0.7202838659286499 pypy before: 0.17805707454681396 after: 0.13431048393249512 In our internal repo, the performance improvement is in seconds. I have used octobus's ASV perf benchmark thing to get the above numbers. I also see some minute perf improvements related to creating a new commit without a new file, but I believe that's just some noise. Differential Revision: https://phab.mercurial-scm.org/D5301

py3: fix couple of division operator to do integer divison Differential Revision: https://phab.mercurial-scm.org/D5305

py3: use dict.items() instead of dict.iteritems() dict.iteritems() does not exist on Python 3. Differential Revision: https://phab.mercurial-scm.org/D5304

py3: convert strings to bytes in tests/test-remotefilelog-histpack.py Differential Revision: https://phab.mercurial-scm.org/D5303

py3: replace str() with pycompat.bytestr() or ('%d' % int) After this patch, test-fastannotate-diffopts.t is about to pass. There are some extra newlines in the output. Differential Revision: https://phab.mercurial-scm.org/D5300

perf: add a `--timing` argument to `perfhelper-tracecopies` The new argument will help picking better pair for benchmarking. See documentation for details.

ui: manage logger instances and event filtering by core ui The setup code in blackbox needs more tweaks since it has lots of black magics. I'll fix them by follow-up patches. To be clear, the goal of this series is to provide a proper way for command server to install its own logger. I need it to debug in-memory repository cache.

extensions: add "uipopulate" hook, called per instance, not per process In short, this is the "reposetup" function for ui. It allows us to modify ui attributes without extending ui.__class__. Before, the only way to do that was to abuse the config dictionary, which is copied across ui instances. See the next patch for usage example.

hgweb: load globally-enabled extensions explicitly Before, extensions were loaded as a side effect of hg.repository() if the hgweb was executed as a CGI/WSGI. I want to make it explicit so that another ui hook can be inserted after extensions.loadall().

tests: sniff for libfuzzer actually being available in test-fuzz-targets.t When I upgraded the FreeBSD buildbot to 11.2 it seems we picked up clang6, but the default clang on FreeBSD doesn't include libfuzzer. I can't find a way to sniff for libfuzzer without running a compile, so here we are. Differential Revision: https://phab.mercurial-scm.org/D5270