fsmonitor can significantly speed up operations on large working
directories. But fsmonitor isn't enabled by default, so naive users
may not realize there is a potential to make Mercurial faster.
This commit introduces a warning to working directory updates when
fsmonitor could be used.
The following conditions must be met:
* Working directory is previously empty
* New working directory adds >= N files (currently 50,000)
* Running on Linux or MacOS
* fsmonitor not enabled
* Warning not disabled via config override
Because of the empty working directory restriction, most users will
only see this warning during `hg clone` (assuming very few users
actually do an `hg up null`).
The addition of a warning may be considered a BC change. However, clone
has printed warnings before. Until recently, Mercurial printed a warning
with the server's certificate fingerprint when it wasn't explicitly
trusted for example. The warning goes to stderr. So it shouldn't
interfere with scripts parsing meaningful output.
The OS restriction was on the advice of Facebook engineers, who only
feel confident with watchman's stability on the supported platforms.
.. feature::
Print warning when fsmonitor isn't being used on a large repository
Differential Revision: https://phab.mercurial-scm.org/D894
Splitting at too small gaps might not be worthwhile. With this changeset,
we stop considering splitting on too small gaps. The threshold is configurable.
We arbitrarily pick 256K as a default value because it seems "okay".
Further testing on various repositories and setups will be needed to tune it.
The option name is 'experimental.sparse-read.min-gap-size`, and replaces
`experimental.sparse-read.min-block-size` which is not used any more.
Before this changesets, a literal '.*:foo$' config would match a registered
'.*:foo$' generic. This is wrong since generic should be matched through
regular exception only. This changeset fixes this problem.
Thanks for to Yuya Nishihara for spotting the issue.
Grouping all evolution related-config under the experimental.evolution
namespace would helps the future migration outside [experimental].
Differential Revision: https://phab.mercurial-scm.org/D1155
Stabilization config items were never part of a release, remove them now that
we cleaned up the evolution related configuration.
Differential Revision: https://phab.mercurial-scm.org/D1154
Update the evolution helpers function to support both old-style configuration and
new-style configuration:
experimental.evolution=all is renamed into experimental.evolution=true
experimental.evolution=createmarkers is renamed into
experimental.evolution.createmarkers=true
experimental.evolution=allowunstable is renamed into
experimental.evolution.allowunstable=true
experimental.evolution=exchange is renamed into
experimental.evolution.exchange=true
We choose to not rename individual config options; keeping the same names
would easy the transition for users but it's something that could be easily
done in the future.
Differential Revision: https://phab.mercurial-scm.org/D1147
We want to split the evolution-related configuration and back-out the renaming
from evolution.* to stabilization.*.
First invert the configuration and aliases, so next changesets will be
cleaner.
Differential Revision: https://phab.mercurial-scm.org/D1146
Now that all known options are declared, we setup a warning to make sure it will
stay this way.
We disable the warning in two tests checking other behavior with random options.
The heuristics algorithm find possible candidates for move/copy and then check
whether they are actually a copy or move. In some cases, there can be lot of
candidates possible which can actually slow down the algorithm.
This patch introduces a config option
`experimental.copytrace.movecandidateslimit` using which one can limit the
candidates to check. The limit defaults to 100.
Thanks to Yuya for suggesting to skip copytracing for that file with a
warning.
Differential Revision: https://phab.mercurial-scm.org/D987
The shelve extensions import and call rebase content without loading the
extension. This is problematic as the config items rebase uses are not
declared and the default value are not set, etc...
The shelve extension should be using core utilities only and the necessary bit
should be moved from rebase into core. In the meantime, I'm taking a small
step to get config registration completed with minimal overhead. The rebase
extension is shipped with core so registering its config option within core is
not a big issue.
This is the last step needed before we can install a warning that enforces all
config to be registered.
We register the merge-tools config section (which has an arbitrary base config
value) and the possible sub-attribute. The sub-attribute has to be registered
first or at the same time otherwise the '.*' item would shadow them.
Merge tools could include "." in their name so we can't constrain any more
than just ".*".
Delta chains can become quite sparse if there is a lot of unrelated data between
relevant pieces. Right now, revlog always reads all the necessary data for the
delta chain in one single read. This can lead to a lot of unrelated data to be
read (see issue5482 for more details).
One can use the `experimental.maxdeltachainspan` option with a large value
(or -1) to easily produce a very sparse delta chain.
This change introduces the ability to slice the chunks retrieval into multiple
reads, skipping large sections of unrelated data. Preliminary testing shows
interesting results. For example the peak memory consumption to read a manifest
on a large repository is reduced from 600MB to 250MB (200MB without
maxdeltachainspan). However, the slicing itself and the multiple reads can have
an negative impact on performance. This is why the new feature is hidden behind
an experimental flag.
Future changesets will add various parameters to control the slicing heuristics.
We hope to experiment a wide variety of repositories during 4.4 and hopefully
turn the feature on by default in 4.5.
As a first try, the algorithm itself is prone to deep changes. However, we wish
to define APIs and have a baseline to work on.
experimental.updatecheck was renamed into commands.update.check, use the
config system to provides the fallback on the old config name instead of
adding more code.
Differential Revision: https://phab.mercurial-scm.org/D1117
Depends on D931.
This patch introduces functions and a config option that will allow a user
to halt the merge if there are failures during a file merge. These functions
will be used in the next patch.
Differential Revision: https://phab.mercurial-scm.org/D932
Rename 'devel.empty-changegroup' to 'devel.warn-empty- changegroup' in order
to clarify it controls a warning message.
No alias is installed since the previous configuration option was not
documented.
.. feature::
New `commands.update.check` feature to adjust constraints on when
`hg update` will allow updates with a dirty working copy.
also
.. bc::
The `experimental.updatecheck` name for the new `commands.update.check`
feature is now deprecated, and will be removed after this release.
Differential Revision: https://phab.mercurial-scm.org/D1070
Some section can contains arbitrary keys (eg: color, alias, extensions). We
add a way to register some generic config items for them. This is necessary to
get all the config registered. We use a regular expression because some sub-
attributes (eg: hooks.xxx.priority) can define default value on their own.
