bundle2: avoid unbound read when seeking
Currently, seekableunbundlepart.seek() will perform a read() during
seek operations. This will allocate a buffer to hold the raw data
over the seek distance. This can lead to very large allocations
and cause performance to suffer.
We change the code to perform read(32768) in a loop to avoid
potentially large allocations.
`hg perfbundleread` on an uncompressed Firefox bundle reveals
a performance impact:
! bundle2 iterparts()
! wall 2.992605 comb 2.990000 user 2.260000 sys 0.730000 (best of 4)
! bundle2 iterparts() seekable
! wall 3.863810 comb 3.860000 user 3.000000 sys 0.860000 (best of 3)
! bundle2 part seek()
! wall 6.213387 comb 6.200000 user 3.350000 sys 2.850000 (best of 3)
! wall 3.820347 comb 3.810000 user 2.980000 sys 0.830000 (best of 3)
Since seekable bundle parts are (only) used by bundlerepo, this /may/
speed up initial loading of bundle-based repos. But any improvement
will likely only be noticed on very large bundles.
Differential Revision: https://phab.mercurial-scm.org/D1394
hide outer repo
$ hg init
Invalid syntax: no value
$ cat > .hg/hgrc << EOF
> novaluekey
> EOF
$ hg showconfig
hg: parse error at $TESTTMP/.hg/hgrc:1: novaluekey (glob)
[255]
Invalid syntax: no key
$ cat > .hg/hgrc << EOF
> =nokeyvalue
> EOF
$ hg showconfig
hg: parse error at $TESTTMP/.hg/hgrc:1: =nokeyvalue (glob)
[255]
Test hint about invalid syntax from leading white space
$ cat > .hg/hgrc << EOF
> key=value
> EOF
$ hg showconfig
hg: parse error at $TESTTMP/.hg/hgrc:1: key=value (glob)
unexpected leading whitespace
[255]
$ cat > .hg/hgrc << EOF
> [section]
> key=value
> EOF
$ hg showconfig
hg: parse error at $TESTTMP/.hg/hgrc:1: [section] (glob)
unexpected leading whitespace
[255]
Reset hgrc
$ echo > .hg/hgrc
Test case sensitive configuration
$ cat <<EOF >> $HGRCPATH
> [Section]
> KeY = Case Sensitive
> key = lower case
> EOF
$ hg showconfig Section
Section.KeY=Case Sensitive
Section.key=lower case
$ hg showconfig Section -Tjson
[
{
"name": "Section.KeY",
"source": "*.hgrc:*", (glob)
"value": "Case Sensitive"
},
{
"name": "Section.key",
"source": "*.hgrc:*", (glob)
"value": "lower case"
}
]
$ hg showconfig Section.KeY -Tjson
[
{
"name": "Section.KeY",
"source": "*.hgrc:*", (glob)
"value": "Case Sensitive"
}
]
$ hg showconfig -Tjson | tail -7
},
{
"name": "*", (glob)
"source": "*", (glob)
"value": "*" (glob)
}
]
Test empty config source:
$ cat <<EOF > emptysource.py
> def reposetup(ui, repo):
> ui.setconfig('empty', 'source', 'value')
> EOF
$ cp .hg/hgrc .hg/hgrc.orig
$ cat <<EOF >> .hg/hgrc
> [extensions]
> emptysource = `pwd`/emptysource.py
> EOF
$ hg config --debug empty.source
read config from: * (glob)
none: value
$ hg config empty.source -Tjson
[
{
"name": "empty.source",
"source": "",
"value": "value"
}
]
$ cp .hg/hgrc.orig .hg/hgrc
Test "%unset"
$ cat >> $HGRCPATH <<EOF
> [unsettest]
> local-hgrcpath = should be unset (HGRCPATH)
> %unset local-hgrcpath
>
> global = should be unset (HGRCPATH)
>
> both = should be unset (HGRCPATH)
>
> set-after-unset = should be unset (HGRCPATH)
> EOF
$ cat >> .hg/hgrc <<EOF
> [unsettest]
> local-hgrc = should be unset (.hg/hgrc)
> %unset local-hgrc
>
> %unset global
>
> both = should be unset (.hg/hgrc)
> %unset both
>
> set-after-unset = should be unset (.hg/hgrc)
> %unset set-after-unset
> set-after-unset = should be set (.hg/hgrc)
> EOF
$ hg showconfig unsettest
unsettest.set-after-unset=should be set (.hg/hgrc)
Test exit code when no config matches
$ hg config Section.idontexist
[1]
sub-options in [paths] aren't expanded
$ cat > .hg/hgrc << EOF
> [paths]
> foo = ~/foo
> foo:suboption = ~/foo
> EOF
$ hg showconfig paths
paths.foo:suboption=~/foo
paths.foo=$TESTTMP/foo
edit failure
$ HGEDITOR=false hg config --edit
abort: edit failed: false exited with status 1
[255]
config affected by environment variables
$ EDITOR=e1 VISUAL=e2 hg config --debug | grep 'ui\.editor'
$VISUAL: ui.editor=e2
$ VISUAL=e2 hg config --debug --config ui.editor=e3 | grep 'ui\.editor'
--config: ui.editor=e3
$ PAGER=p1 hg config --debug | grep 'pager\.pager'
$PAGER: pager.pager=p1
$ PAGER=p1 hg config --debug --config pager.pager=p2 | grep 'pager\.pager'
--config: pager.pager=p2
verify that aliases are evaluated as well
$ hg init aliastest
$ cd aliastest
$ cat > .hg/hgrc << EOF
> [ui]
> user = repo user
> EOF
$ touch index
$ unset HGUSER
$ hg ci -Am test
adding index
$ hg log --template '{author}\n'
repo user
$ cd ..
alias has lower priority
$ hg init aliaspriority
$ cd aliaspriority
$ cat > .hg/hgrc << EOF
> [ui]
> user = alias user
> username = repo user
> EOF
$ touch index
$ unset HGUSER
$ hg ci -Am test
adding index
$ hg log --template '{author}\n'
repo user
$ cd ..