util: lower water mark when removing nodes after cost limit reached
See the inline comment for the reasoning here. This is a pretty
common strategy for garbage collectors, other cache-like primtives.
The performance impact is substantial:
$ hg perflrucachedict --size 4 --gets 1000000 --sets 1000000 --mixed 1000000 --costlimit 100
! inserts w/ cost limit
! wall 1.659181 comb 1.650000 user 1.650000 sys 0.000000 (best of 7)
! wall 1.722122 comb 1.720000 user 1.720000 sys 0.000000 (best of 6)
! mixed w/ cost limit
! wall 1.139955 comb 1.140000 user 1.140000 sys 0.000000 (best of 9)
! wall 1.182513 comb 1.180000 user 1.180000 sys 0.000000 (best of 9)
$ hg perflrucachedict --size 1000 --gets 1000000 --sets 1000000 --mixed 1000000 --costlimit 10000
! inserts
! wall 0.679546 comb 0.680000 user 0.680000 sys 0.000000 (best of 15)
! sets
! wall 0.825147 comb 0.830000 user 0.830000 sys 0.000000 (best of 13)
! inserts w/ cost limit
! wall 25.105273 comb 25.080000 user 25.080000 sys 0.000000 (best of 3)
! wall 1.724397 comb 1.720000 user 1.720000 sys 0.000000 (best of 6)
! mixed
! wall 0.807096 comb 0.810000 user 0.810000 sys 0.000000 (best of 13)
! mixed w/ cost limit
! wall 12.104470 comb 12.070000 user 12.070000 sys 0.000000 (best of 3)
! wall 1.190563 comb 1.190000 user 1.190000 sys 0.000000 (best of 9)
$ hg perflrucachedict --size 1000 --gets 1000000 --sets 1000000 --mixed 1000000 --costlimit 10000 --mixedgetfreq 90
! inserts
! wall 0.711177 comb 0.710000 user 0.710000 sys 0.000000 (best of 14)
! sets
! wall 0.846992 comb 0.850000 user 0.850000 sys 0.000000 (best of 12)
! inserts w/ cost limit
! wall 25.963028 comb 25.960000 user 25.960000 sys 0.000000 (best of 3)
! wall 2.184311 comb 2.180000 user 2.180000 sys 0.000000 (best of 5)
! mixed
! wall 0.728256 comb 0.730000 user 0.730000 sys 0.000000 (best of 14)
! mixed w/ cost limit
! wall 3.174256 comb 3.170000 user 3.170000 sys 0.000000 (best of 4)
! wall 0.773186 comb 0.770000 user 0.770000 sys 0.000000 (best of 13)
$ hg perflrucachedict --size 100000 --gets 1000000 --sets 1000000 --mixed 1000000 --mixedgetfreq 90 --costlimit 5000000
! gets
! wall 1.191368 comb 1.190000 user 1.190000 sys 0.000000 (best of 9)
! wall 1.195304 comb 1.190000 user 1.190000 sys 0.000000 (best of 9)
! inserts
! wall 0.950995 comb 0.950000 user 0.950000 sys 0.000000 (best of 11)
! inserts w/ cost limit
! wall 1.589732 comb 1.590000 user 1.590000 sys 0.000000 (best of 7)
! sets
! wall 1.094941 comb 1.100000 user 1.090000 sys 0.010000 (best of 9)
! mixed
! wall 0.936420 comb 0.940000 user 0.930000 sys 0.010000 (best of 10)
! mixed w/ cost limit
! wall 0.882780 comb 0.870000 user 0.870000 sys 0.000000 (best of 11)
This puts us ~2x slower than caches without cost accounting. And for
read-heavy workloads (the prime use cases for caches), performance is
nearly identical.
In the worst case (pure write workloads with cost accounting enabled),
we're looking at ~1.5us per insert on large caches. That seems "fast
enough."
Differential Revision: https://phab.mercurial-scm.org/D4505
test command parsing and dispatch
$ hg init a
$ cd a
Redundant options used to crash (issue436):
$ hg -v log -v
$ hg -v log -v x
$ echo a > a
$ hg ci -Ama
adding a
Missing arg:
$ hg cat
hg cat: invalid arguments
hg cat [OPTION]... FILE...
output the current or given revision of files
options ([+] can be repeated):
-o --output FORMAT print output to file with formatted name
-r --rev REV print the given revision
--decode apply any matching decode filter
-I --include PATTERN [+] include names matching the given patterns
-X --exclude PATTERN [+] exclude names matching the given patterns
(use 'hg cat -h' to show more help)
[255]
Missing parameter for early option:
$ hg log -R 2>&1 | grep 'hg log'
hg log: option -R requires argument
hg log [OPTION]... [FILE]
(use 'hg log -h' to show more help)
"--" may be an option value:
$ hg -R -- log
abort: repository -- not found!
[255]
$ hg log -R --
abort: repository -- not found!
[255]
$ hg log -T --
-- (no-eol)
$ hg log -T -- -k nomatch
Parsing of early options should stop at "--":
$ hg cat -- --config=hooks.pre-cat=false
--config=hooks.pre-cat=false: no such file in rev cb9a9f314b8b
[1]
$ hg cat -- --debugger
--debugger: no such file in rev cb9a9f314b8b
[1]
Unparsable form of early options:
$ hg cat --debugg
abort: option --debugger may not be abbreviated!
[255]
Parsing failure of early options should be detected before executing the
command:
$ hg log -b '--config=hooks.pre-log=false' default
abort: option --config may not be abbreviated!
[255]
$ hg log -b -R. default
abort: option -R has to be separated from other options (e.g. not -qR) and --repository may only be abbreviated as --repo!
[255]
$ hg log --cwd .. -b --cwd=. default
abort: option --cwd may not be abbreviated!
[255]
However, we can't prevent it from loading extensions and configs:
$ cat <<EOF > bad.py
> raise Exception('bad')
> EOF
$ hg log -b '--config=extensions.bad=bad.py' default
*** failed to import extension bad from bad.py: bad
abort: option --config may not be abbreviated!
[255]
$ mkdir -p badrepo/.hg
$ echo 'invalid-syntax' > badrepo/.hg/hgrc
$ hg log -b -Rbadrepo default
hg: parse error at badrepo/.hg/hgrc:1: invalid-syntax
[255]
$ hg log -b --cwd=inexistent default
abort: $ENOENT$: 'inexistent'
[255]
$ hg log -b '--config=ui.traceback=yes' 2>&1 | grep '^Traceback'
Traceback (most recent call last):
$ hg log -b '--config=profiling.enabled=yes' 2>&1 | grep -i sample
Sample count: .*|No samples recorded\. (re)
Early options can't be specified in [aliases] and [defaults] because they are
applied before the command name is resolved:
$ hg log -b '--config=alias.log=log --config=hooks.pre-log=false'
hg log: option -b not recognized
error in definition for alias 'log': --config may only be given on the command
line
[255]
$ hg log -b '--config=defaults.log=--config=hooks.pre-log=false'
abort: option --config may not be abbreviated!
[255]
Shell aliases bypass any command parsing rules but for the early one:
$ hg log -b '--config=alias.log=!echo howdy'
howdy
Early options must come first if HGPLAIN=+strictflags is specified:
(BUG: chg cherry-picks early options to pass them as a server command)
#if no-chg
$ HGPLAIN=+strictflags hg log -b --config='hooks.pre-log=false' default
abort: unknown revision '--config=hooks.pre-log=false'!
[255]
$ HGPLAIN=+strictflags hg log -b -R. default
abort: unknown revision '-R.'!
[255]
$ HGPLAIN=+strictflags hg log -b --cwd=. default
abort: unknown revision '--cwd=.'!
[255]
#endif
$ HGPLAIN=+strictflags hg log -b --debugger default
abort: unknown revision '--debugger'!
[255]
$ HGPLAIN=+strictflags hg log -b --config='alias.log=!echo pwned' default
abort: unknown revision '--config=alias.log=!echo pwned'!
[255]
$ HGPLAIN=+strictflags hg log --config='hooks.pre-log=false' -b default
abort: option --config may not be abbreviated!
[255]
$ HGPLAIN=+strictflags hg log -q --cwd=.. -b default
abort: option --cwd may not be abbreviated!
[255]
$ HGPLAIN=+strictflags hg log -q -R . -b default
abort: option -R has to be separated from other options (e.g. not -qR) and --repository may only be abbreviated as --repo!
[255]
$ HGPLAIN=+strictflags hg --config='hooks.pre-log=false' log -b default
abort: pre-log hook exited with status 1
[255]
$ HGPLAIN=+strictflags hg --cwd .. -q -Ra log -b default
0:cb9a9f314b8b
$ HGPLAIN=+strictflags hg --cwd .. -q --repository a log -b default
0:cb9a9f314b8b
$ HGPLAIN=+strictflags hg --cwd .. -q --repo a log -b default
0:cb9a9f314b8b
For compatibility reasons, HGPLAIN=+strictflags is not enabled by plain HGPLAIN:
$ HGPLAIN= hg log --config='hooks.pre-log=false' -b default
abort: pre-log hook exited with status 1
[255]
$ HGPLAINEXCEPT= hg log --cwd .. -q -Ra -b default
0:cb9a9f314b8b
[defaults]
$ hg cat a
a
$ cat >> $HGRCPATH <<EOF
> [defaults]
> cat = -r null
> EOF
$ hg cat a
a: no such file in rev 000000000000
[1]
$ cd "$TESTTMP"
OSError "No such file or directory" / "The system cannot find the path
specified" should include filename even when it is empty
$ hg -R a archive ''
abort: *: '' (glob)
[255]
#if no-outer-repo
No repo:
$ hg cat
abort: no repository found in '$TESTTMP' (.hg not found)!
[255]
#endif
#if rmcwd
Current directory removed:
$ mkdir $TESTTMP/repo1
$ cd $TESTTMP/repo1
$ rm -rf $TESTTMP/repo1
The output could be one of the following and something else:
chg: abort: failed to getcwd (errno = *) (glob)
abort: error getting current working directory: * (glob)
sh: 0: getcwd() failed: $ENOENT$
Since the exact behavior depends on the shell, only check it returns non-zero.
$ HGDEMANDIMPORT=disable hg version -q 2>/dev/null || false
[1]
#endif