compression: introduce an official `format.revlog-compression` option
This option supersedes the `experiment.format.compression` option. The value
currently supported are zlib (default) and zstd (if Mercurial was compiled with
zstd support).
The option gained an explicit reference to `revlog` since this is the target
usage here. Different storage methods might require different compression
strategies.
In our tests, using zstd give a significant CPU usage improvement (both
compression and decompressing) while keeping similar repository size.
Zstd as other interresting mode (dictionnary, pre-text, etc…) that are probably
worth exploring. However, just plain switching from zlib to zstd provide a large
benefit.
from __future__ import absolute_import, print_function
import os
from mercurial import (
commands,
extensions,
ui as uimod,
)
ignore = {b'highlight', b'win32text', b'factotum', b'beautifygraph'}
try:
import sqlite3
del sqlite3 # unused, just checking that import works
except ImportError:
ignore.add(b'sqlitestore')
if os.name != 'nt':
ignore.add(b'win32mbcs')
disabled = [ext for ext in extensions.disabled().keys() if ext not in ignore]
hgrc = open(os.environ["HGRCPATH"], 'wb')
hgrc.write(b'[extensions]\n')
for ext in disabled:
hgrc.write(ext + b'=\n')
hgrc.close()
u = uimod.ui.load()
extensions.loadall(u)
extensions.populateui(u)
globalshort = set()
globallong = set()
for option in commands.globalopts:
option[0] and globalshort.add(option[0])
option[1] and globallong.add(option[1])
for cmd, entry in commands.table.items():
seenshort = globalshort.copy()
seenlong = globallong.copy()
for option in entry[1]:
if ((option[0] and option[0] in seenshort) or
(option[1] and option[1] in seenlong)):
print("command '" + cmd + "' has duplicate option " + str(option))
seenshort.add(option[0])
seenlong.add(option[1])