commands: config option to control bundle compression level
Currently, bundle compression uses the default compression level
for the active compression engine. The default compression level
is tuned as a compromise between speed and size.
Some scenarios may call for a different compression level. For
example, with clone bundles, bundles are generated once and used
several times. Since the cost to generate is paid infrequently,
server operators may wish to trade extra CPU time for better
compression ratios.
This patch introduces an experimental and undocumented config
option to control the bundle compression level. As the inline
comment says, this approach is a bit hacky. I'd prefer for
the compression level to be encoded in the bundle spec. e.g.
"zstd-v2;complevel=15." However, given that the 4.1 freeze is
imminent, I'm not comfortable implementing this user-facing
change without much time to test and consider the implications.
So, we're going with the quick and dirty solution for now.
Having this option in the 4.1 release will enable Mozilla to
easily produce and test zlib and zstd bundles with non-default
compression levels in production. This will help drive future
development of the feature and zstd integration with Mercurial.
# Disable the $CAP wire protocol capability.
if test -z "$CAP"
then
echo "CAP environment variable not set."
fi
cat > notcapable-$CAP.py << EOF
from mercurial import extensions, peer, localrepo
def extsetup():
extensions.wrapfunction(peer.peerrepository, 'capable', wrapcapable)
extensions.wrapfunction(localrepo.localrepository, 'peer', wrappeer)
def wrapcapable(orig, self, name, *args, **kwargs):
if name in '$CAP'.split(' '):
return False
return orig(self, name, *args, **kwargs)
def wrappeer(orig, self):
# Since we're disabling some newer features, we need to make sure local
# repos add in the legacy features again.
return localrepo.locallegacypeer(self)
EOF
echo '[extensions]' >> $HGRCPATH
echo "notcapable-$CAP = `pwd`/notcapable-$CAP.py" >> $HGRCPATH