revlog: break up compression of large deltas
Python's zlib apparently makes an internal copy of strings passed to
compress(). To avoid this, compress strings 1M at a time, then join
them at the end if the result would be smaller than the original.
For initial commits of large but compressible files, this cuts peak
memory usage nearly in half.
#!/bin/sh
commit()
{
msg=$1
p1=$2
p2=$3
if [ "$p1" ]; then
hg up -qC $p1
fi
if [ "$p2" ]; then
HGMERGE=true hg merge -q $p2
fi
echo >> foo
hg commit -d '0 0' -qAm "$msg" foo
}
hg init repo
cd repo
echo '[extensions]' > .hg/hgrc
echo 'hgext.parentrevspec =' >> .hg/hgrc
commit '0: add foo'
commit '1: change foo 1'
commit '2: change foo 2a'
commit '3: change foo 3a'
commit '4: change foo 2b' 1
commit '5: merge' 3 4
commit '6: change foo again'
hg log --template '#rev#:#node|short# #parents#\n'
echo
lookup()
{
for rev in "$@"; do
printf "$rev: "
hg id -nr $rev
done
true
}
tipnode=`hg id -ir tip`
echo 'should work with tag/branch/node/rev'
for r in tip default $tipnode 6; do
lookup "$r^"
done
echo
echo 'some random lookups'
lookup "6^^" "6^^^" "6^^^^" "6^^^^^" "6^^^^^^" "6^1" "6^2" "6^^2" "6^1^2" "6^^3"
lookup "6~" "6~1" "6~2" "6~3" "6~4" "6~5" "6~42" "6~1^2" "6~1^2~2"
echo
echo 'with a tag "6^" pointing to rev 1'
hg tag -l -r 1 "6^"
lookup "6^" "6^1" "6~1" "6^^"
echo
echo 'with a tag "foo^bar" pointing to rev 2'
hg tag -l -r 2 "foo^bar"
lookup "foo^bar" "foo^bar^"